• Publications
  • Conferences & Events
  • Professional Learning
  • Science Standards
  • Awards & Competitions
  • Daily Do Lesson Plans
  • Free Resources
  • American Rescue Plan
  • For Preservice Teachers

NCCSTS Case Collection

  • Partner Jobs in Education
  • Interactive eBooks+
  • Digital Catalog
  • Regional Product Representatives
  • e-Newsletters
  • Bestselling Books
  • Latest Books
  • Popular Book Series
  • Prospective Authors
  • Web Seminars
  • Exhibits & Sponsorship
  • Conference Reviewers
  • National Conference • Denver 24
  • Leaders Institute 2024
  • Submit a Proposal
  • Latest Resources
  • Professional Learning Units & Courses
  • For Districts
  • Online Course Providers
  • Schools & Districts
  • College Professors & Students
  • The Standards
  • Teachers and Admin
  • Toshiba/NSTA ExploraVision
  • Junior Science & Humanities Symposium
  • Teaching Awards
  • Climate Change
  • Earth & Space Science
  • New Science Teachers
  • Early Childhood
  • Middle School
  • High School
  • Postsecondary
  • Informal Education
  • Journal Articles
  • Lesson Plans
  • e-newsletters
  • Science & Children
  • Science Scope
  • The Science Teacher
  • Journal of College Sci. Teaching
  • Connected Science Learning
  • NSTA Reports
  • Next-Gen Navigator
  • Science Update
  • Teacher Tip Tuesday
  • Trans. Sci. Learning

MyNSTA Community

  • My Collections

Case Study Listserv

Permissions & Guidelines

Submit a Case Study

Resources & Publications

Enrich your students’ educational experience with case-based teaching

The NCCSTS Case Collection, created and curated by the National Center for Case Study Teaching in Science, on behalf of the University at Buffalo, contains nearly a thousand peer-reviewed case studies on a variety of topics in all areas of science.

Cases (only) are freely accessible; subscription is required for access to teaching notes and answer keys.

Subscribe Today

Browse Case Studies

Latest Case Studies

NSF logo

Development of the NCCSTS Case Collection was originally funded by major grants to the University at Buffalo from the National Science Foundation , The Pew Charitable Trusts , and the U.S. Department of Education .

  • UB Directory

buffalo case study caffeine

News Center

Professor in a conference room teaching a small group of students.

Researchers will help set standards and develop tools to ensure AI’s role for social good nationwide.

Voters walking into a polling location to cast their ballots.

Findings involve the novel repurposing of existing theoretical political models to show how a compulsory voting system could reduce the distance between the proposed policies of two major political parties.

Zoom image: University at Buffalo chemist Luis Colón works with a student in his lab in UB's Natural Sciences Complex. Credit: Douglas Levere/University at Buffalo

SUNY Distinguished Professor honored for longstanding commitment to increase diversity in chemical sciences. 

Flags outside the United Nations headquarters in New York City.

UB will gain global recognition and representation at the United Nations, and will be involved in advocacy efforts to help monitor and implement international agreements.

Study finds no association between caffeine intake and invasive breast cancer risk

Two women enjoy coffee while sitting together on a couch.

By David J. Hill

Release Date: September 27, 2021

BUFFALO, N.Y. — Researchers from the University at Buffalo conducted a study of nearly 80,000 postmenopausal women in the U.S. to determine whether caffeine consumption from coffee and tea has any association with invasive breast cancer.

The average age when U.S. women reach menopause, 51, also happens to coincide with the age group — 50- to 64-year-olds — that has the highest reported caffeine consumption. In addition to that, the average age of breast cancer diagnosis in the U.S. is 62.

This overlap of age at menopause, age at diagnosis of breast cancer and age with high caffeine consumption gave greater weight to the importance of clarifying whether caffeine intake impacts breast cancer risk in postmenopausal women.

It does not, according to the UB researchers’ findings, published in August in the International Journal of Cancer .

“From our literature review, many studies have found significant associations between coffee and/or tea consumption and reduced breast cancer incidence whereas a few studies have reported elevated risk. Our study, however, found no association,” said study first author Christina KH Zheng, who worked on the study while completing her master’s in epidemiology at UB. She is now a surgical resident in the MedStar Baltimore general surgery program.

“About 85% of Americans drink at least one caffeinated beverage a day. It is important for the public to know whether consumption of caffeinated beverages has beneficial or harmful effects on breast cancer, the most common type of cancer and second-leading cause of cancer death for U.S. women,” said Lina Mu , MD, PhD, the study’s senior author, who is an associate professor of epidemiology and environmental health at UB.

“The overlap of age at diagnosis of breast cancer and age with high consumption of caffeine, and the inconsistent findings from previous studies motivated us to study whether this lifestyle factor could affect breast cancer risk in postmenopausal women,” said Kexin Zhu, a study co-first author and epidemiology PhD student in UB’s School of Public Health and Health Professions.

Researchers looked at a sample of 79,871 participants in the Women’s Health Initiative Observational Study. Participants have for decades now completed yearly health questionnaires that help researchers learn more about diet and exercise habits, as well as disease, and any possible linkages.

After a median follow-up of 16 years, there were 4,719 cases of invasive breast cancer identified.

At first glance, women who reported drinking two to three cups of caffeinated coffee per day had a 12% higher risk of invasive breast cancer compared to non-drinkers. But that association was not statistically significant after adjusting for lifestyle factors, such as smoking and alcohol consumption.

“Seeing null results after adjusting for lifestyle, demographic and reproductive factors informs us of the complexity that is the relationship between caffeine intake and invasive breast cancer risk,” Zheng said.

“Some lifestyle factors, like drinking alcohol and physical activity, might be associated with both coffee intake and breast cancer risk,” Zhu explained. “Therefore, they might confound the initial positive associations. After we took the lifestyle factors into account, the results suggested that regular coffee drinking might not have an impact on invasive breast cancer risk.”

The risk of invasive breast cancer was even higher — 22% — for women who reported drinking two to three cups of decaffeinated coffee each day. It was slightly lower when adjusted for lifestyle variables (smoking history, alcohol consumption, physical activity, etc.), and the association was not statistically significant when further accounting for reproductive variables such as family history of breast cancer and number of children

The researchers were unable to determine if the elevated risk is due to the decaffeinated nature of the coffee, the amount consumed, or another factor unique to this population that was not accounted for in the study.

The researchers did not observe a significant association between overall tea consumption and invasive breast cancer. Additional research needs to be done in order to understand whether different types of teas have different effects on breast cancer risk, Zhu said.

Additional co-authors on the paper are all from UB’s Department of Epidemiology and Environmental Health and include Jean Wactawski-Wende , PhD, dean of the School of Public Health and Health Professions and SUNY Distinguished Professor; Jo L. Freudenheim , PhD, SUNY Distinguished Professor; Michael LaMonte , PhD, research professor; and Kathleen Hovey, data manager/statistician.

Media Contact Information

David J. Hill Director of Media Relations Public Health, Architecture, Urban and Regional Planning, Sustainability Tel: 716-645-4651 [email protected]

UB Faculty Experts

Head shot of Timothy Cook in a laboratory.

Timothy Cook

Professor of Chemistry

Expertise: molecular self-assembly, photochemistry, fluorescence, phosphorescence, batteries, alternative energy

Phone:  716-645-4327

Email: [email protected]

Portrait of David A. Mmilling, University at Buffalo medical education expert.

David A. Milling

Senior Associate Dean for Student and Academic Affairs in the Jacobs School of Medicine and Biomedical Sciences

Expertise:  medical education; clinical skills; multicultural affairs and cultural competency in medicine; diversity in the medical profession

Phone:  716-829-2802

Email:  [email protected]

Contact:  Milling can also be reached through Ellen Goldbaum in University Communications at 716-645-4605 or  [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or  [email protected] .

Head shot of Surajit Sen, University at Buffalo professor of physics.

Surajit Sen

Professor of Physics

Expertise: wave behavior, granular systems, quasi-equilibrium, nonequilibrium and chaotic phenomena, collisions, shock mitigation, sociophysics

Phone:  716-645-6151, 716-907-4961

Email: [email protected]

Portrait of Yan Liu, University at Buffalo Chinese history expert, with a focus on the history of Chinese medicine, food and spices and comparative medicine.

Associate Professor of History

Expertise:  history of Chinese medicine, food and spices; history of epidemics; history of the senses; comparative historical perspectives in medicine

Phone:  716-645-8404

Email:  [email protected]

Head shot of Anne B. Curtis.

Anne B. Curtis

SUNY Distinquished Professor

Expertise: heart health, heart rhythm abnormalities, atrial fibrillation, cardiac devices, pacemakers, implantable cardiac defibrillators, cardiac problems in winter

Phone: 716-859-4828

Email: [email protected]

Portrait of Luis A. Colón, University at Buffalo separation science, analytical chemistry, and STEM diversity expert.

Luis A. Colón

A. Conger Goodyear Professor of Chemistry

Expertise: analytical chemistry, separation science, liquid chromatography, diversity in STEM, mentoring students of color

Phone:  716-645-4213

Email: [email protected]

Portrait of Letitia Thomas, University at Buffalo STEM education and STEM diversity expert.

Letitia Thomas

Assistant Dean for Diversity in the University at Buffalo School of Engineering and Applied Sciences

Expertise: STEM education and pipelines; women and students of color in STEM; sociology of education; social justice; social networks; microaggressions

Phone:  716-645-3071

Email: [email protected]

Head shot of Mark Hicar, University at Buffalo expert on pediatric infectious disease, including measles and the flu.

Mark Daniel Hicar

Associate Professor of Pediatrics

Expertise:  pediatric infectious diseases, viral infections, antibody responses against HIV, Kawasaki disease

Phone:  716-323-0150

Email: [email protected]

Head shot of Melanie Green.

Melanie Green

Chair and Professor of Communication

Expertise:  persuasion, power of narrative, storytelling, online friendships, trust and deception online

Phone:  716-645-1508

Email:  [email protected]

Portrait of David M. Holmes, University at Buffalo global health equity and medicine and spirituality expert.

David M. Holmes

Clinical Associate Professor of Family Medicine

Expertise:  global health, health care for underserved communities and human trafficking victims, spirituality in health, religious exemptions for vaccines, addiction medicine, wilderness medicine, travel medicine

Email:  [email protected]

Contact:  David M. Holmes can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or  [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or  [email protected] .

Head shot of Lynn T. Kozlowski.

Lynn T. Kozlowski

Professor and Dean Emeritus of Community Health and Health Behavior

Expertise:  nicotine addiction, smoking, vaping, tobacco and e-cigarette policy, FDA regulations on nicotine products

Phone:  716-829-6770

Email: [email protected]

Portrait of Stephanie Choi.

Stephanie Choi

Postdoctoral Associate, Asia Research Institute

Expertise:  K-pop music, global gender politics, affective labor, and political economies in digital media

Phone:  716-645-2457

Email:  [email protected]

Head shot of David Schmid.

David Schmid

Associate Professor of English

Expertise: popular culture, cultural studies, celebrity, crime, manhood, the monstrous, contemporary British and American fiction, American literary and cultural treatments of the city

Phone: 716-645-0679

Email: [email protected]

Portrait of Sarah L. Berga, University at Buffalo reproductive medicine expert.

Sarah L. Berga

Professor and Chair of Obstetrics and Gynecology

Expertise:  infertility; stress-induced amenorrhea; in vitro fertilization, reproductive hormones and brain health; COVID-19 vaccines during pregnancy

Email:  [email protected]

Contact:  Sarah L. Berga can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or  [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or  [email protected] .

Head shot of Lynn Shanahan, University at Buffalo literacy expert.

Lynn Shanahan

Associate Professor of of Learning and Instruction

Expertise: childhood literacy; literacy, technology and multimodality; STEM and urban education

Phone:  716-645-4028

Email: [email protected]

Head shot of Andrew Whittaker.

Andrew Whittaker

SUNY Distinguished Professor of Civil, Structural and Environmental Engineering

Expertise: earthquake engineering; seismic protective systems; blast engineering; bridge engineering; infrastructure; design and assessment of nuclear power plants; performance-based engineering; risk engineering

Phone: 716-645-4364

Email:  [email protected]

Head shot of Derek Daniels, University at Buffalo thirst and ingestive behavior expert.

Derek Daniels

Professor and Chair of Biological Sciences

Expertise:  science of thirst; science of food, water and salt intake; ingestive/eating behaviors

Phone:  716-645-0264

Email:  [email protected]

Bina Ramamurthy, research associate professor of computer science.

Bina Ramamurthy

Professor of Teaching in Computer Science and Engineering

Expertise: Blockchain; blockchain and cryptocurrency (Bitcoin, Ether) and non-fungible tokens; data-intensive computing; big data platforms

Phone:  716-645-3182

Email: [email protected]

Head shot of Peter Winkelstein, University at Buffalo faculty expert on electronic health records.

Peter Winkelstein

Executive Director of the Institute for Healthcare Informatics

Expertise: electronic health/medical records; medical informatics; ethics and informatics; computer modeling

Phone:  716-881-7546. Winkelstein can also be reached through Ellen Goldbaum in University Communications at 716-645-4605 or [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or [email protected] .

Email: [email protected]

Shamim M. Islam.

Shamim M. Islam

Clinical Associate Professor of Pediatrics

Expertise:  pediatric infectious diseases, antimicrobial stewardship, global antimicrobial resistance, local and international infectious disease control, tropical medicine, medical and public health education

Email:  [email protected]

Contact: Shamim M. Islam can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or [email protected] .

Portrait of Sourav Sengupta, University at Buffalo child and adolescent mental health expert.

Sourav Sengupta

Associate Professor of Psychiatry and Pediatrics

Expertise:  Child and adolescent mental health; children’s and adolescents’ use of technology, including screen time

Email:  [email protected]

Contact: Sourav Sengupta can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or [email protected], or Douglas Sitler in University Communications at 716-645-9069 or [email protected].

Portrait of Isok Kim, University at Buffalo mental health and refugee-related trauma expert.

Associate Professor of Social Work

Expertise:  mental health and wellbeing among Asian Americans; refugee-related trauma; post-resettlement challenges; culturally responsive mental health services

Phone:  716-645-1252

Email:  [email protected]

Head shot of Catherine Cook-Cottone, UB yoga and mindfulness researcher.

Catherine Cook-Cottone

Professor of Counseling, School and Educational Psychology

Expertise: yoga, mindfulness, embodied self-regulation, eating disorders, anxiety-based disorders

Phone:  716-645-1128

Email: [email protected]  

Head shot of Jacob Neiheisel, University at Buffalo faculty expert on campaigns and elections.

Jacob Neiheisel

Associate Professor of Political Science

Expertise:  political communication, campaigns, electoral strategy, religion and politics, the U.S. Christian right, voter turnout, voting rights, election administration, electoral reforms, the U.S. presidency

Phone:  716-645-8439

Email: [email protected]

Head shot of Henry-Louis Taylor Jr., University at Buffalo urban development and gentrification expert.

Henry-Louis Taylor Jr.

Director of the Center for Urban Studies

Expertise: urban development, housing, gentrification, underdeveloped neighborhoods, shrinking cities, race and class, U.S.-Cuba relations

Phone:  716-829-5458

Email:  [email protected]

Head shot of Jamie Ostrov, University at Buffalo bullying and victimization expert.

Jamie Ostrov

Professor of Psychology

Expertise: subtypes of aggression and victimization, developmental psychopathology, media effects on children, peer relationships, applied developmental psychology

Phone: 716-645-3680

Email: [email protected]

Portrait of Joan Linder, University at Buffalo art and drawing expert. Copyright Liz Linder Photography.

Joan Linder

Professor of Art

Expertise:  drawing, consumption and mass production, mundane objects, modern life, Love Canal and other toxic sites, environmental art, feminist art, power, public art

Phone:  716-645-0539

Email:  [email protected]

Head shot of Xiaozhong Wen.

Xiaozhong Wen

Assistant Professor of Pediatrics

Expertise: diet and health in infants and young children, origins of obesity, smoking cessation during pregnancy

Phone:  716-829-6811

Email:  [email protected]

Head shot of Steven Dubovsky.

Steven L. Dubovsky

Professor Emeritus of Psychiatry

Expertise:  trauma, depression, mood disorders, psychosis, psychosomatic medicine

Phone:  716-898-5940

Email:  [email protected]

Head shot of Xiufeng Liu, University at Buffalo expert on STEM education.

Xiufeng Liu

SUNY Distinguished Professor of Learning and Instruction

Expertise: STEM education, including student achievement, assessment and evaluation, and STEM teaching in colleges and universities; science and the public

Phone:  716-645-4050

Email: [email protected]

Portrait of Stephanie Fredrick, University at Buffalo bullying and cyberbullying expert.

Stephanie Fredrick

Associate Director of the Alberti Center for Bullying Abuse Prevention

Expertise:  bullying, cyberbullying, youth mental health, bullying interventions

Phone:  716-645-1141

Email:  [email protected]

Head shot of Kemper E. Lewis.

Kemper E. Lewis

Dean of the School of Engineering and Applied Sciences

Expertise: advanced manufacturing, mass customization, engineering design

Phone:  716-645-2682

Email: [email protected]

Head shot of Haiqing Lin, University at Buffalo carbon capture expert.

Haiqing Lin

Professor of Chemical and Biological Engineering

Expertise: separation science, carbon capture, water purification, polymers, materials science

Phone:  716-645-1856

Email: [email protected]

Head shot of Stelios Andreadis, University at Buffalo regenerative medicine and tissue engineering expert.

Stelios Andreadis

SUNY Distinguished Professor of Chemical and Biological Engineering

Expertise: regenerative medicine, tissue engineering, stem cells, vascular grafts

Phone:  716-645-1202

Email: [email protected]

Head shot of Frank Scannapieco, University at Buffalo oral health and dental plaque expert.

Frank A. Scannapieco, DMD, PhD

Chair of Oral Biology

Expertise: link between oral and overall health; oral health care in hospitals and nursing homes; dental plaque

Phone:  716-829-3373

Email: [email protected]

Head shot of Amanda Nickerson.

Amanda Nickerson

Director of the Alberti Center for Bullying Abuse Prevention

Expertise: school violence, bullying prevention and intervention, parent and peer relationships, assessment and treatment of emotional and behavioral disorders

Phone: 716-645-1532

Email: [email protected]

Head shot of Marc Halfon.

Marc Halfon

Professor of Biochemistry

Expertise: genetics; gene expression; gene drive; genome editing; mosquito genome; cell growth, differentiation and development

Phone:  716-829-3126

Email: [email protected]

Head shot of Barbara Wejnert.

Barbara Wejnert

Professor of Global Gender and Sexuality Studies

Expertise: spread of democracy since 1800, democratic transitions and sustainability, Eastern European politics and political movements, democracy and inequality in a globalized world

Phone:  716-645-0787

Email: [email protected]

Head shot of Salvatore Rappoccio.

Salvatore Rappoccio

Expertise:  particle physics, particle detectors

Phone:  716-645-6250

Email:  [email protected]

Head shot of Dave Hostler, University at Buffalo human performance expert.

Dave Hostler

Chair of Exercise and Nutrition Sciences

Expertise: effect of diving on human health; environmental physiology; hyperthermia; hypothermia; firefighter and emergency responder health and safety

Phone:  716-829-6795

Email: [email protected]

Head shot of Richard Salvi.

Richard Salvi

SUNY Distinguished Professor Emeritus of Communicative Disorders and Sciences

Expertise: tinnitus, hearing, noise-induced hearing loss, hyperacusis, central auditory system

Phone:  716-829-5310

Email: [email protected]

Head shot of Timothy Murphy, University at Buffalo infectious diseases expert.

Timothy F. Murphy

SUNY Distinguished Professor of Medicine

Expertise:  infectious diseases, chronic obstructive pulmonary disease (COPD), vaccine development, children’s ear infections, health disparities, clinical and translational science

Phone:  716-881-8911

Email: [email protected]

Head shot of Peter Rogerson.

Peter A. Rogerson

SUNY Distinguished Professor of Geography

Expertise:  demographics, population trends, baby boomers, spatial statistics, epidemiology, geographic centers

Phone:  716-645-0483

Email: [email protected]

Portrait of Sayanti Mukherjee, University at Buffalo predictive analytics and critical infrastructure systems expert.

Sayanti Mukherjee

Assistant Professor of Industrial and Systems Engineering

Expertise:  resilient sociotechnical systems, predictive analytics, risk-informed decision-making, public health and health care, electrical grid and energy, climate change impact assessment

Phone:  716-645-4699

Email:  [email protected]

Portrait of Allison Brashear, University at Buffalo medical education and spasticity and dystonia expert.

Allison Brashear

Vice President for Health Sciences and Dean of the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo

Expertise:  medical education and research, diversity in medicine, women in medicine, community engagement and health equity, clinical trials, treatment of rare neurologic disorders, spasticity and dystonia.

Contact: Allison Brashear can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or [email protected] .

Head shot of Shira Gabriel, University at Buffalo social psychology and social connection expert.

Shira Gabriel

Professor of Psychology

Expertise: social psychology, social connections, sense of self, the need to belong, comfort food

Phone:  716-645-0227

Email: [email protected]

Head shot of Arun Lakshmanan, University at Buffalo marketing and consumer attention expert.

Arun Lakshmanan

Associate Professor of Marketing

Expertise: sensory marketing and visual perception; consumer attention and learning; new product use and design; advertising and social media

Contact: Arun Lakshmanan can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Eva Zurek.

Tevfik Kosar

Professor of Computer Science and Engineering

Expertise:  big data, cloud computing, distributed systems, high-performance computing, green computing, energy-efficient systems

Phone:  716-645-2323

Email: [email protected]

Head shot of Claire E. Cameron, University at Buffalo early childhood education and child development expert.

Claire E. Cameron

Associate Professor of Learning and Instruction

Expertise: early childhood education, childhood development, educational psychology, classroom management

Phone:  716-645-4075

Email: [email protected]

Head shot of Matthew Dimick.

Matthew Dimick

Professor of Law

Expertise:  income inequality, tax and welfare policy as it relates to income inequality, corporations, employment law, labor law

Phone: 716-645-7968

Email: [email protected]

Robert Miletich.

Robert Miletich

Interim Chair and Professor of Nuclear Medicine

Expertise: nuclear medicine, nuclear neurology, brain scans and other neuroimaging techniques and neurodegenerative diseases

Phone:  716-838-5889

Email: [email protected]

Head shot of Susan Green.

Susan Green

Co-director of the Institute on Trauma and Trauma-Informed Care

Expertise: trauma, trauma-informed care in organizations and service delivery systems

Phone: 716-645-1249

Email: [email protected]

Szu-Yin (Jennifer) Wu.

Szu-Yin (Jennifer) Wu

Clinical Assistant Professor of Finance

Expertise: corporate finance; mergers and acquisitions; shareholder activism; corporate governance; investment management

Contact: Szu-Yin (Jennifer) Wu can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Larry White.

Larry White

Assistant Professor of Information Science

Expertise: library management, leadership, policy, organizational performance  

Phone:  716-645-1473

Email: [email protected]

Head shot of Darryl Somayaji, University at Buffalo cancer care expert.

Darryl Somayaji

Assistant Professor of Nursing

Expertise: cancer care and health disparities in underserved communities

Phone:  716-829-2178

Email: [email protected]

Head shot of Mark Bartholomew.

Mark Bartholomew

Expertise: intellectual property, copyright, trademarks, cyber law, artificial intelligence and copyright law, cybersecurity bills, net neutrality, advertising law

Phone: 716-645-5959

Email:  [email protected]

Head shot of Teresa Quattrin, University at Buffalo clinical trials and childhood diabetes and obesity expert.

Teresa Quattrin

Senior Associate Dean for Research Integration

Expertise:  childhood diabetes; family-based obesity treatment; clinical translational research and trials, with a focus on diversity and inclusion

Phone:  716-323-0170

Email: [email protected]

Inho Suk.

Associate Professor of Accounting and Law

Expertise: corporate voluntary disclosures; accounting fraud; environmental, social and governance (ESG) accounting; mergers and acquisitions (consolidation) accounting; executive and employee turnover; accounting-marketing interface

Contact:  Inho Suk can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Timothy Maynes, University at Buffalo employee performance and productivity expert.

Timothy Maynes

Associate Professor of Organization and Human Resources

Expertise: employee-driven innovation and change; employee productivity, engagement and performance; effective team functioning (especially in sports)

Contact:  Timothy Maynes can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Beata Csatho.

Beata Csatho

Professor of Geology

Expertise: climate change, sea level rise, Greenland Ice Sheet, Antarctic ice loss, glaciers, remote sensing, using satellite data and laser altimetry to measure the Earth

Phone:  716-645-4325

Email: [email protected]

Head shot of Albert Titus, University at Buffalo wearable technology expert.

Albert H. Titus

Professor of Biomedical Engineering

Expertise: biomedical engineering, wearable technology, biosensors, smart sensors

Phone:  716-645-1019

Email: [email protected]

Head shot of Heather Orom, University at Buffalo health disparities expert.

Heather Orom

Associate Professor of Community Health and Health Behavior

Expertise: health disparities, illness risk perception

Phone:  716-829- 6682

Email: [email protected]

Portrait of Charlotte Lindqvist.

Amanda Aykanian

Assistant Professor of Social Work

Expertise:  homelessness, including how social policies and programs affect unhoused people; homeless service systems and workforce issues; social welfare history and policy; social service program implementation

Phone:  716-645-1270

Email:  [email protected]

Head shot of Yu-Ping Chang, University at Buffalo caregiving and dementia expert.

Yu-Ping Chang

Patricia H. and Richard E. Garman Endowed Professor of Nursing

Expertise: mental health; substance abuse and addiction; family caregiving and dementia

Phone:  716-829-2015

Email: [email protected]

Dominik Roesch.

Dominik Roesch

Associate Professor of Finance

Expertise: arbitrage, liquidity, international markets, market efficiency, market microstructure

Contact:  Dominik Roesch can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Mike Mingcheng Wei.

Mike Mingcheng Wei

Associate Professor of Operations Management and Strategy

Expertise: supply chain management; dynamic pricing; revenue management; strategic consumer behavior; online learning and decision-making; online recommendation systems; assortment optimization; high-dimensional machine learning

Contact: Mike Mingcheng Wei can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Portrait of Y. Chris Li, University at Buffalo electrochemistry and waste conversion expert.

Y. Chris Li

Assistant Professor of Chemistry

Expertise:  electrochemistry, waste conversion, transforming greenhouse gases into useful products, chemistry of CO2, plastics

Phone:  716-645-4285

Email:  [email protected]

Head shot of Wendy Quinton.

Wendy Quinton

Clinical Professor of Psychology

Expertise: prejudice, discrimination, stigma, social identity, student adjustment and success, international students

Phone:  716-645-0230

Email: [email protected]

Head shot of John Cerne.

Expertise:  physics in everyday life, condensed matter physics, high-temperature superconductors, graphene, optics

Phone:  716-645-2542

Email:  [email protected]

Head shot of Murali Ramanathan, professor of pharmaceutical sciences.

Murali Ramanathan

Professor of Pharmaceutical Sciences

Expertise: multiple sclerosis (MS), disease-modifying drugs

Phone:  716-645-4846

Email: [email protected]

Head shot of Yingjie Hu, University at Buffalo faculty expert on GIScience and data mining.

Assistant Professor of Geography

Expertise: GIScience, spatial analysis, natural language processing, artificial intelligence, machine learning, data mining, big data

Phone:  716-645-1820

Email: [email protected]

Head shot of Yotam Ophir, University at Buffalo media effects and health, science and political communication expert.

Yotam Ophir

Assistant Professor of Communication

Expertise: misinformation; persuasion; effect of media content on audiences, including in health, science, politics and terrorism

Phone:  716-645-1158

Email: [email protected]

Head shot of Johannes Hachmann, University at Buffalo computational chemistry and materials design expert.

Johannes Hachmann

Associate Professor of Chemical and Biological Engineering

Expertise: computational chemistry; molecular and materials modeling; cheminformatics; machine learning; big data; materials discovery and design

Phone:  716-645-1524

Email:  [email protected]

Headshot of Amit Goyal.

SUNY Distinguished Professor and Empire Innovation Professor of Chemical and Biological Engineering

Expertise: renewable energy; environmental and water issues; high-temperature superconductivity; materials science

Phone:  716-645-5920

Email: [email protected]

Portrait of Venu Govindaraju.

Venu Govindaraju

Vice President for Research and Economic Development

Expertise:  artificial intelligence, including document analysis recognition, machine learning, pattern recognition, biometrics and generative AI

Phone:  716-645-3321

Email: [email protected]

Head shot of Sanjukta Das Smith.

Sunyee Yoon

Assistant Professor of Marketing

Expertise:  social status and mobility; socially responsible consumption; products that promote animal welfare; consumer behavior

Contact:  Sunyee Yoon can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Erin Hatton, University at Buffalo labor, workforce and gig economy expert.

Erin Hatton

Professor of Sociology

Expertise: labor movements, gig economy, job security, coerced labor, pay for college athletes, minimum wage, workfare

Phone:  716-645-8476

Email: [email protected]

Head shot of Elizabeth Mazzolini, University at Buffalo environmental studies, waste studies and consumerism expert.

Elizabeth Mazzolini

Expertise: Mountaineering deaths, climbing technology, consumerism, material culture, garbage, culture of waste

Phone:  716-645-0691

Email: [email protected]

Portrait of Guyora Binder, University at Buffalo criminal law expert.

Guyora Binder

SUNY Distinguished Professor of Law and Hodgson Russ Faculty Scholar

Expertise:  criminal law, felony murder, homicide, jurisprudence, legal theory, international law

Phone:  716-645-2673

Email:  [email protected]

Portrait of Yini Zhang, University at Buffalo political communication and social media expert.

Expertise:  social media, political communication, misinformation, online activism, impact of social media on journalism and democracy

Phone:  716-645-0954

Email:  [email protected]

Portrait of Mickey Sperlich, University at Buffalo midwifery, childbirth and trauma expert.

Mickey Sperlich

Expertise: trauma and mental health challenges in pregnancy, childbirth and the postpartum period; women’s health; midwifery

Phone:  716-645-9087

Email: [email protected]

Portrait of Anthony O'Rourke, University at Buffalo criminal law and procedure expert.

Anthony O’Rourke

Joseph W. Belluck and Laura L. Aswad Professor of Civil Justice

Expertise: criminal law and procedure, inequality in the criminal justice system

Phone:  716-645-3097

Email:  [email protected]

Head shot of Joana Gaia, University at Buffalo digital security and privacy expert.

Clinical Assistant Professor of Management Science and Systems

Expertise: health information systems; business intelligence; digital security and privacy; data analytics; emergency management; girls and STEM careers

Contact: Joana Gaia can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Kenneth E. Leonard.

Kenneth E. Leonard

Director of the Clinical and Research Institute on Addictions

Expertise: alcohol, substance abuse and aggression; effects of substance use on marriage, families and relationships; interpersonal (domestic) violence; medical and recreational marijuana; prescription painkillers  

Phone:  716-887-2566

Email: [email protected]

Portrait of Tiffany Karalis Noel, University at Buffalo education expert, with expertise in multiculturalism, social inequity and belongingness in education.

Tiffany Karalis Noel

Clinical Assistant Professor of Learning and Instruction

Expertise: sociocultural inequity in education, teacher preparation and retention, mentoring in higher education

Phone:  716-645-2455

Email: [email protected]

Portrait of Laura Rusche, University at Buffalo genetics and yeast biology expert.

Laura Rusche

Professor of Biological Sciences

Expertise:  yeast, genomics, genetics, gene expression, chromosomes, DNA, RNA, chromatin, sirtuins

Phone:  716-645-5198

Email:  [email protected]

John Violanti at night in front of a blurred police car with lights on.

John M. Violanti

Research Professor of Epidemiology and Environmental Health

Expertise: police stress, health and suicide; PTSD

Phone:  716-829-5481

Email: [email protected]

Head shot of Michael Poulin, University at Buffalo caregiving, stress and generosity expert.

Michael J. Poulin

Associate Professor of Psychology

Expertise: empathy, human generosity, stress, caregiving

Phone: 716-645-0518

Email: [email protected]

Head shot of Ryan Rish, University at Buffalo expert on the literacy practices of adolescents.

Ryan M. Rish

Assistant Professor of Learning and Instruction

Expertise: adolescent literacy practices; culture and identity in learning; teaching social issues

Phone:  716-645-4042

Email: [email protected]

Head shot of Ryan Muldoon, University at Buffalo faculty expert on diversity.

Ryan Muldoon

Associate Professor of Philosophy

Expertise: social and political philosophy, diversity, international development policy, social norms, behavior change, ethics

Phone:  716-645-0140

Email: [email protected]

Head shot of Will Kinney, University at Buffalo physics, cosmology and astronomy expert.

William H. Kinney

Expertise: astronomy, cosmology, cosmic inflation, cosmic microwave background, dark matter, dark energy, solar eclipses, public outreach in science

Phone: 716-645-5360

Email: [email protected]

Head shot of Charlotte Lindqvist, University at Buffalo evolutionary biology expert.

Joann Sands

Clinical Assistant Professor of Nursing

Expertise: disaster response education and training; emergency preparedness and management; the role of nurses in disasters

Phone:  716-829-2342

Email: [email protected]

Head shot of Paresh Dandona, University at Buffalo faculty expert on diabetes and obesity.

Paresh Dandona

Expertise:  diabetes; obesity; endocrinology; insulin, testosterone and other hormone treatments; anti-inflammatory agents

Phone:  Dandona can be contacted through Ellen Goldbaum in UB Media Relations at 716-645-4605 or  [email protected]

Email:  [email protected]

Portrait of Conor Dowling.

Conor Dowling

Professor of Political Science

Expertise:  U.S. elections, public opinion, campaign finance, political parties, effects of political scandal

Phone:  716-645-8436

Email: [email protected]

Head shot of Robert G. Shibley.

Robert G. Shibley

SUNY Distinguished Professor

Expertise: urban design and planning, urban revitalization, postindustrial cities, Buffalo and Western New York, the Rust Belt

Phone: 716-829-3981

Email: [email protected]

Contact: Shibley can also be reached through David Hill in UB Media Relations (716-645-4651, [email protected] ) or Rachel Teaman in the School of Architecture and Planning (716-829-3794, [email protected] ).

Portrait of Ralph H. Benedict, University at Buffalo multiple sclerosis and brain injury expert.

Ralph H. Benedict

Professor of Neurology

Expertise:  multiple sclerosis (MS); impact of MS, concussion and other brain diseases on personality, cognition and psychiatric stability

Email:  [email protected]

Contact:  Ralph H. Benedict can be reached through Ellen Goldbaum in University Communications at 716-645-4605 or  [email protected] , or Douglas Sitler in University Communications at 716-645-9069 or  [email protected] .

Head shot of Victor Albert, University at Buffalo plant evolution expert.

Victor Albert

Empire Innovation Professor of Biological Sciences

Expertise:  plant evolutionary biology; evolution of carnivorous plants; genomes of Amborella, avocado, birch, coffee and gardenia; comparative genomics; junk DNA

Phone: 716-645-4983

Email: [email protected]

Head shot of Helen A. Nellie Drew.

Helen A. “Nellie” Drew

Director of the Center for the Advancement of Sport

Expertise:  sports law, including student-athletes’ name, image and likeness (NIL), antitrust laws, collective bargaining, discipline of athletes, drug testing, NCAA compliance and Title IX; diversity in sport

Phone:  716-645-2071

Email: [email protected]

Brandon Szerwo.

Brandon Szerwo

Assistant Professor of Accounting and Law

Expertise: financial reporting and audit quality, corporate governance, financial regulation, management disclosures, auditor disclosures, financial accounting

Contact: Brandon Szerwo can be reached most quickly through Jackie Ghosen in the School of Management Communications Office at 716-645-2833 or [email protected] .

Head shot of Kafuli Agbemenu, University at Buffalo reproductive health expert.

Kafuli Agbemenu

Expertise:  reproductive health in vulnerable populations

Phone:  716-829-6023

Email:  [email protected]

UB on Futurity.org

Futurity logo.

  • 2/8/24 Social media use tied to inflammation
  • 12/5/23 Postmenopausal caregivers may have lower death risk
  • 10/26/23 Being weird can be a blessing and curse for Shark Tank entrepreneurs

Caffeine’s Dirty Little Secret

“How much is too much?” is an impossible question.

A mug of coffee surrounded by a min–max dial

Listen to this article

Listen to more stories on curio

This article was featured in the One Story to Read Today newsletter. Sign up for it here .

On Tuesday, curiosity finally got the best of me. How potent could Panera’s Charged Lemonades really be? Within minutes of my first sip of the hyper-caffeinated drink in its strawberry-lemon-mint flavor, I understood why memes have likened it to an illicit drug. My vision sharpened; sweat slicked my palms.

Laced with more caffeine than a typical energy drink, Panera’s Charged Lemonade has been implicated in two wrongful-death lawsuits since it was introduced in 2022. Though both customers who died had health issues that made them sensitive to caffeine, a third lawsuit this month alleges that the lemonade gave an otherwise healthy 27-year-old lasting heart problems. Following the second death, Panera denied that the drink was the cause, but in light of the lawsuits, it has added warnings about the drink , reduced its caffeine content , and removed the option for customers to serve themselves .

All the attention on Panera’s Charged Lemonade has resurfaced an age-old question: How much caffeine is too much? You won’t find a simple answer anywhere. Caffeine consumption is widely considered to be beneficial because it mostly is—boosting alertness, productivity, and even mood. But there is a point when guzzling caffeine tips over into uncomfortable, possibly unhealthy territory. The problem is that defining this point in discrete terms is virtually impossible. In the era of extreme caffeine, this is a dangerous way to live.

Most people don’t have to worry about dying after drinking a Charged Lemonade. The effects, though uncomfortable, usually seem to be minor. After drinking half of mine, I was so wired that I couldn’t make sense of the thoughts ricocheting around my brain for the next few hours. Caffeine routinely leads to jitteriness, nervousness, sweating, insomnia, and rapid heartbeat. If mild, such symptoms can be well worth the benefits.

But consuming too much caffeine can have serious health impacts. High doses—more than 1,000 milligrams a day —can result in a state of intoxication known as caffeinism . The symptoms can be severe: People can “develop seizures and life-threatening irregularities of the heartbeat,” and some die, David Juurlink, a toxicology professor at the University of Toronto who also works at the Ontario Poison Centre, told me. “It’s one of the dirty little secrets, I’m afraid, of caffeine.” Juurlink said he occasionally gets calls about people, typically high-school or college students, who have ingested multiple caffeine pills on a dare or in a suicide attempt.

You’re unlikely to ingest that much caffeine from beverages alone, yet the increasing availability of highly caffeinated products makes it more of a possibility than ever before. Besides Panera’s Charged Lemonade, dozens of energy drinks contain similar amounts of caffeine, and some come in candy-inspired flavors such as Bubblicious and Sour Patch Kids. Less potent but highly snackable products include c affeinated coffee cubes , energy chews, marshmallows , mints, ice pops , and even vapes . Consumed quickly and in rapid succession, these foods can lead to potentially toxic caffeine intake “because your body hasn’t had time to tell you to stop,” Jennifer Temple, a professor at the University of Buffalo who studies caffeine use, told me.

More than ever, we need a way to track our caffeine consumption, but we don’t seem to have any good options. In all of the lawsuits against Panera, the basic argument is this: Had the company more adequately warned customers of the drink’s caffeine content, perhaps no one would have been hurt. But most of us just aren’t used to thinking about caffeine in numerical terms the way we do with calories and alcohol by volume (ABV). Caffeine intake is generally something that’s not measured but experienced : I know, for example, that a double espresso from the office coffee machine will give me the shakes. But even though I knew how much caffeine is in a Charged Lemonade, I had no idea how much of it I could drink before having the same reaction.

The FDA does have a recommended daily caffeine limit of 400 milligrams, the equivalent of about four or five cups of coffee. “Based on the relevant science and information available,” a spokesperson told me, consuming that much each day “does not raise safety concerns” for most adults, except for people who are pregnant or nursing, or have concerns related to their health conditions or the medication they take. The agency, however, doesn’t require food labels to note caffeine content, though some companies include that information voluntarily.

But the numbers are helpful only up to a point. The FDA’s daily recommendation is a “rough guideline” that can’t be used as a universal standard, because “it’s not safe for everybody,” Temple said. For one person, 237 milligrams could mean a trip to the hospital; for another, that would just be breakfast. The effect of a given caffeine dose “varies tremendously from person to person based upon their historical pattern of use and also their genetics,” Juurlink told me.

Although people generally aren’t aware of the amounts of caffeine they consume, they tend to develop a good sense of how much they can handle, Temple said. But usually, this knowledge is product-specific; when trying a new caffeine product, the effect can be hard to predict. Part of the problem is that the amount of caffeine in products varies dramatically, even among drinks that may seem similar: A 12-ounce Americano from McDonald’s contains 71 milligrams of caffeine, but the same drink at Starbucks contains 150 milligrams. The caffeine in popular energy drinks ranges from 75 milligrams (Ocean Spray Cran-Energy) to 316 milligrams (Redline Xtreme), according to the Center for Science in the Public Interest .

Contrast this with alcohol, which tends to be served in conventional units regardless of brand: a can of beer, a glass of wine, or a shot of liquor, all of which have roughly the same ability to intoxicate. Having a standard unit to gauge consumption isn’t foolproof—consuming too much alcohol is still far too easy—but it is nevertheless helpful for thinking about how much you’re ingesting, as well as the differences between beverages. Without such a metric for caffeine, consuming new beverages takes on a daredevil quality. Sipping the Charged Lemonade felt like venturing into the Wild West of caffeine.

The reason we aren’t good at thinking about caffeine is that historically, we’ve never really had to think that hard about it. Sure, one too many espressos might have occasionally put someone over the edge, but caffeine was consumed and sold in amounts that didn’t require as much thought or caution. “A generation ago, you didn’t have all these energy drinks,” so people didn’t grow up learning about safe caffeine consumption the way they may have done for alcohol, Darin Detwiler, a food-policy expert at Northeastern University, told me.

Compounding the concern is the fact that energy drinks are popular with kids, who are more susceptible to caffeine’s effects because they’re smaller. Kids tend to drink even more when drinks are labeled as highly caffeinated, Temple said, and the fact that they contain huge amounts of sugar to mask the bitter taste of caffeine adds to their appeal. Last year, a child reportedly went into cardiac arrest after drinking a can of Prime Energy—prompting Senator Chuck Schumer to call on the FDA to investigate its “eye-popping caffeine content.”

Nothing else in our daily diet is quite like caffeine. Certainly people swear by it, and its benefits are clear: Research shows that it can improve cognitive performance, speed up reaction time, and boost logical reasoning, and it may even reduce the risk of Parkinson’s, diabetes , liver disease, and cancer . But for a substance so ubiquitous that it’s called the most widely used drug in the world , our grasp of how to maximize its benefits is feeble at best. Even the most seasoned coffee drinkers sometimes unintentionally get too wired; as new, more highly caffeinated products become available, instances of caffeine drinkers overdoing it will probably become more common. Perhaps the best we can do is learn how much of each drink we can handle, one super-charged sip at a time.

chemical formula for caffeine with three coffee beans on the side

Many of us can’t imagine starting the day without a cup of coffee. One reason may be that it supplies us with a jolt of caffeine, a mild stimulant to the central nervous system that quickly boosts our alertness and energy levels. [1] Of course, coffee is not the only caffeine-containing beverage. Read on to learn more about sources of caffeine, and a review of the research on this stimulant and health.

Absorption and Metabolism of Caffeine

The chemical name for the bitter white powder known as caffeine is 1,3,7 trimethylxanthine. Caffeine is absorbed within about 45 minutes after consuming, and peaks in the blood anywhere from 15 minutes to 2 hours. [2] Caffeine in beverages such as coffee, tea, and soda is quickly absorbed in the gut and dissolves in both the body’s water and fat molecules. It is able to cross into the brain. Food or food components, such as fibers, in the gut can delay how quickly caffeine in the blood peaks. Therefore, drinking your morning coffee on an empty stomach might give you a quicker energy boost than if you drank it while eating breakfast.

Caffeine is broken down mainly in the liver. It can remain in the blood anywhere from 1.5 to 9.5 hours, depending on various factors. [2] Smoking speeds up the breakdown of caffeine, whereas pregnancy and oral contraceptives can slow the breakdown. During the third trimester of pregnancy, caffeine can remain in the body for up to 15 hours. [3]

People often develop a “caffeine tolerance” when taken regularly, which can reduce its stimulant effects unless a higher amount is consumed. When suddenly stopping all caffeine, withdrawal symptoms often follow such as irritability, headache, agitation, depressed mood, and fatigue. The symptoms are strongest within a few days after stopping caffeine, but tend to subside after about one week. [3] Tapering  the amount gradually may help to reduce side effects.

Sources of Caffeine

Caffeine is naturally found in the fruit, leaves, and beans of coffee , cacao, and guarana plants. It is also added to beverages and supplements. There is a risk of drinking excess amounts of caffeinated beverages like soda and energy drinks because they are taken chilled and are easy to digest quickly in large quantities.

  • Coffee. 1 cup or 8 ounces of brewed coffee contains about 95 mg caffeine. The same amount of instant coffee contains about 60 mg caffeine. Decaffeinated coffee contains about 4 mg of caffeine. Learn more about coffee .
  • Espresso. 1 shot or 1.5 ounces contains about 65 mg caffeine.
  • Tea. 1 cup of black tea contains about 47 mg caffeine. Green tea contains about 28 mg. Decaffeinated tea contains 2 mg, and herbal tea contains none. Learn more about tea .
  • Soda. A 12-ounce can of regular or diet dark cola contains about 40 mg caffeine. The same amount of Mountain Dew contains 55 mg caffeine.
  • Chocolate (cacao) . 1 ounce of dark chocolate contains about 24 mg caffeine, whereas milk chocolate contains one-quarter of that amount.
  • Guarana. This is a seed from a South American plant that is processed as an extract in foods, energy drinks, and energy supplements. Guarana seeds contain about four times the amount of caffeine as that found in coffee beans. [4] Some drinks containing extracts of these seeds can contain up to 125 mg caffeine per serving.
  • Energy drinks. 1 cup or 8 ounces of an energy drink contains about 85 mg caffeine. However the standard energy drink serving is 16 ounces, which doubles the caffeine to 170 mg. Energy shots are much more concentrated than the drinks; a small 2 ounce shot contains about 200 mg caffeine. Learn more about energy drinks .
  • Supplements. Caffeine supplements contain about 200 mg per tablet, or the amount in 2 cups of brewed coffee.

Recommended Amounts

In the U.S., adults consume an average of 135 mg of caffeine daily, or the amount in 1.5 cups of coffee (1 cup = 8 ounces). [5] The U.S. Food and Drug Administration considers 400 milligrams (about 4 cups brewed coffee) a safe amount of caffeine for healthy adults to consume daily. However, pregnant women should limit their caffeine intake to 200 mg a day (about 2 cups brewed coffee), according to the American College of Obstetricians and Gynecologists.

The American Academy of Pediatrics suggests that children under age 12 should not consume any food or beverages with caffeine. For adolescents 12 and older, caffeine intake should be limited to no more than 100 mg daily. This is the amount in two or three 12-ounce cans of cola soda.

Caffeine and Health

Caffeine is associated with several health conditions. People have different tolerances and responses to caffeine, partly due to genetic differences. Consuming caffeine regularly, such as drinking a cup of coffee every day, can promote caffeine tolerance in some people so that the side effects from caffeine may decrease over time. Although we tend to associate caffeine most often with coffee or tea, the research below focuses mainly on the health effects of caffeine itself. Visit our features on coffee , tea , and energy drinks for more health information related to those beverages.

Caffeine can block the effects of the hormone adenosine, which is responsible for deep sleep . Caffeine binds to adenosine receptors in the brain, which not only lowers adenosine levels but also increases or decreases other hormones that affect sleep, including dopamine, serotonin, norepinephrine, and GABA. [2] Levels of melatonin, another hormone promoting sleep, can drop in the presence of caffeine as both are metabolized in the liver. Caffeine intake later in the day close to bedtime can interfere with good sleep quality. Although developing a caffeine tolerance by taking caffeine regularly over time may lower its disruptive effects, [1] those who have trouble sleeping may consider minimizing caffeine intake later in the day and before going to bed.

In sensitive individuals, caffeine can increase anxiety at doses of 400 mg or more a day (about 4 cups of brewed coffee). High amounts of caffeine may cause nervousness and speed up heart rate, symptoms that are also felt during an anxiety attack. Those who have an underlying anxiety or panic disorder are especially at risk of overstimulation when overloading on caffeine.

Caffeine stimulates the heart, increases blood flow, and increases blood pressure temporarily, particularly in people who do not usually consume caffeine. However, strong negative effects of caffeine on blood pressure have not been found in clinical trials, even in people with hypertension, and cohort studies have not found that coffee drinking is associated with a higher risk of hypertension. Studies also do not show an association of caffeine intake and atrial fibrillation (abnormal heart beat), heart disease , or stroke. [3]

Caffeine is often added to weight loss supplements to help “burn calories.” There is no evidence that caffeine causes significant weight loss. It may help to boost energy if one is feeling fatigued from restricting caloric intake, and may reduce appetite temporarily. Caffeine stimulates the sympathetic nervous system, which plays a role in suppressing hunger, enhancing satiety, and increasing the breakdown of fat cells to be used for energy. [6] Cohort studies following large groups of people suggest that a higher caffeine intake is associated with slightly lower rates of weight gain in the long term. [3] However, a fairly large amount of caffeine (equivalent to 6 cups of coffee a day) may be needed to achieve a modest increase in calorie “burn.” Additional calories obtained from cream, milk, or sweetener added to a caffeinated beverage like coffee or tea can easily negate any calorie deficit caused by caffeine.

Caffeine can cross the placenta, and both mother and fetus metabolize caffeine slowly. A high intake of caffeine by the mother can lead to prolonged high caffeine blood levels in the fetus. Reduced blood flow and oxygen levels may result, increasing the risk of miscarriage and low birth weight. [3] However, lower intakes of caffeine have not been found harmful during pregnancy when limiting intakes to no more than 200 mg a day. A review of controlled clinical studies found that caffeine intake, whether low, medium, or high doses, did not appear to increase the risk of infertility. [7]

Most studies on liver disease and caffeine have specifically examined coffee intake. Caffeinated coffee intake is associated with a lower risk of liver cancer, fibrosis, and cirrhosis. Caffeine may prevent the fibrosis (scarring) of liver tissue by blocking adenosine, which is responsible for the production of collagen that is used to build scar tissue. [3]

Studies have shown that higher coffee consumption is associated with a lower risk of gallstones. [8] Decaffeinated coffee does not show as strong a connection as caffeinated coffee. Therefore, it is likely that caffeine contributes significantly to this protective effect. The gallbladder is an organ that produces bile to help break down fats; consuming a very high fat diet requires more bile, which can strain the gallbladder and increase the risk of gallstones. It is believed that caffeine may help to stimulate contractions in the gallbladder and increase the secretion of cholecystokinin, a hormone that speeds the digestion of fats.

Caffeine may protect against Parkinson’s disease. Animal studies show a protective effect of caffeine from deterioration in the brain. [3] Prospective cohort studies show a strong association of people with higher caffeine intakes and a lower risk of developing Parkinson’s disease. [9]

Caffeine has a similar action to the medication theophylline, which is sometimes prescribed to treat asthma. They both relax the smooth muscles of the lungs and open up bronchial tubes, which can improve breathing. The optimal amount of caffeine needs more study, but the trials reviewed revealed that even a lower caffeine dose of 5 mg/kg of body weight showed benefit over a placebo. [10] Caffeine has also been used to treat breathing difficulties in premature infants. [3]

Caffeine stimulates the release of a stress hormone called epinephrine, which causes liver and muscle tissue to release its stored glucose into the bloodstream, temporarily raising blood glucose levels. However, regular caffeine intake is not associated with an increased risk of diabetes . In fact, cohort studies show that regular coffee intake is associated with a lower risk of type 2 diabetes , though the effect may be from the coffee plant compounds rather than caffeine itself, as decaffeinated coffee shows a similar protective effect. [3] Other observational studies suggest that caffeine may protect and preserve the function of beta cells in the pancreas, which are responsible for secreting insulin. [11]

Signs of Toxicity

Caffeine toxicity has been observed with intakes of 1.2 grams or more in one dose. Consuming 10-14 grams at one time is believed to be fatal. Caffeine intake up to 10 grams has caused convulsions and vomiting, but recovery is possible in about 6 hours. Side effects at lower doses of 1 gram include restlessness, irritability, nervousness, vomiting, rapid heart rate, and tremors.

Toxicity is generally not seen when drinking caffeinated beverages because a very large amount would need to be taken within a few hours to reach a toxic level (10 gm of caffeine is equal to about 100 cups of brewed coffee). Dangerous blood levels are more often seen with overuse of caffeine pills or tablets. [3]

Did You Know?

  • Caffeine is not just found in food and beverages but in various medications. It is often added to analgesics (pain relievers) to provide faster and more effective relief from pain and headaches. Headache or migraine pain is accompanied by enlarged inflamed blood vessels; caffeine has the opposite effect of reducing inflammation and narrowing blood vessels, which may relieve the pain.
  • Caffeine can interact with various medications. It can cause your body to break down a medication too quickly so that it loses its effectiveness. It can cause a dangerously fast heart beat and high blood pressure if taken with other stimulant medications. Sometimes a medication can slow the metabolism of caffeine in the body, which may increase the risk of jitteriness and irritability, especially if one tends to drink several caffeinated drinks throughout the day. If you drink caffeinated beverages daily, talk with your doctor about potential interactions when starting a new medication.

cup of coffee

Energy Drinks

  • Clark I, Landolt HP. Coffee, caffeine, and sleep: A systematic review of epidemiological studies and randomized controlled trials. Sleep medicine reviews . 2017 Feb 1;31:70-8. *Disclosure: some of HPL’s research has been supported by Novartis Foundation for Medical-Biological Research.
  • Institute of Medicine (US) Committee on Military Nutrition Research. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington (DC): National Academies Press (US); 2001. 2, Pharmacology of Caffeine. Available from: https://www.ncbi.nlm.nih.gov/books/NBK223808/
  • van Dam RM, Hu FB, Willett WC. Coffee, Caffeine, and Health.  NEJM .  2020 Jul 23; 383:369-378
  • Moustakas D, Mezzio M, Rodriguez BR, Constable MA, Mulligan ME, Voura EB. Guarana provides additional stimulation over caffeine alone in the planarian model. PLoS One . 2015 Apr 16;10(4):e0123310.
  • Drewnowski A, Rehm CD. Sources of caffeine in diets of US children and adults: trends by beverage type and purchase location. Nutrients . 2016 Mar;8(3):154.
  • Harpaz E, Tamir S, Weinstein A, Weinstein Y. The effect of caffeine on energy balance. Journal of basic and clinical physiology and pharmacolog y. 2017 Jan 1;28(1):1-0.
  • Bu FL, Feng X, Yang XY, Ren J, Cao HJ. Relationship between caffeine intake and infertility: a systematic review of controlled clinical studies.  BMC Womens Health . 2020;20(1):125.
  • Zhang YP, Li WQ, Sun YL, Zhu RT, Wang WJ. Systematic review with meta‐analysis: coffee consumption and the risk of gallstone disease. Alimentary pharmacology & therapeutics . 2015 Sep;42(6):637-48.
  • Hong CT, Chan L, Bai CH. The Effect of Caffeine on the Risk and Progression of Parkinson’s Disease: A Meta-Analysis. Nutrients . 2020 Jun;12(6):1860.
  • Welsh EJ, Bara A, Barley E, Cates CJ. Caffeine for asthma.  Cochrane Database Syst Rev . 2010;2010(1):CD001112.
  • Lee S, Min JY, Min KB. Caffeine and Caffeine Metabolites in Relation to Insulin Resistance and Beta Cell Function in US Adults. Nutrients . 2020 Jun;12(6):1783.

Last reviewed July 2020

Terms of Use

The contents of this website are for educational purposes and are not intended to offer personal medical advice. You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The Nutrition Source does not recommend or endorse any products.

Caffeine and Its Health Effects

How is that daily cup of coffee impacting your health?

This article is based on reporting that features expert sources.

If you're one of the millions of Americans who can't really get the day going without a steaming cup of coffee, rest assured you're definitely not alone. An awful lot of people are dependent on that morning java to wake up and be ready to tackle the day.

For many people, it's the caffeine in coffee that helps them wake up and get moving. "Caffeine is a naturally

barista making latte art, shot focus in cup of milk and coffee, vintage filter image

Getty Images

occurring substance found in more than 60 plants," says Dr. Sophia Tolliver, clinical assistant professor of family medicine at the Ohio State University Wexner Medical Center in Columbus.

Sources of Caffeine

Caffeine can be found in a wide variety of foods and drinks, including:

  • Coffee beans.
  • Tea leaves.
  • Cacao, cocoa and chocolate products.
  • Guarana seeds.
  • Energy drinks .
  • Matcha powder .
  • Pre-workout powders.

Though coffee has been around for centuries, and humans have been reaching for plants to get a buzz for much longer, caffeine was first isolated from coffee by Friedlieb Ferdinand Runge, a German chemist. In 1819, he became the first to isolate and purify caffeine, which he discovered by studying Arabian mocha beans given to him by Johann Wolfgang von Goethe, the famous German poet. Since then, study into the effects of this chemical have expanded. "Caffeine can have both beneficial and detrimental side effects, depending on dose," says Lisa Cooper, a registered dietitian with Orlando Health in Florida. "If taken in moderation, caffeine can increase alertness and reduce tiredness. It can also improve athletic performance by delaying fatigue."

In fact, caffeine is classed as "a central nervous stimulant," that alters your focus and can make you more alert, Tolliver says.

Caffeine isn't regulated the way some drugs are because it's so widely distributed in various common foods and drinks, and it sometimes turns up where you least expect it. It's used as an additive in some drinks, such as seltzers and sports drinks, as an alternative to coffee that gives you a caffeine buzz without the bitter taste of coffee.

Despite its general ubiquity and the sometimes lax approach to its potential effects, you should handle caffeine and caffeinated beverages with care as they can impact your health and well-being, both negatively and positively.

Health Benefits of Caffeine

Nutrition science has at various times both vilified and extolled the virtues of caffeine and coffee. Some studies have noted detrimental effects of coffee and caffeine, but sometimes these studies "did not take into consideration that those who drank coffee tended to smoke or were sedentary," Tolliver says.

More recent studies have tried to control for these factors and have noted that coffee and caffeine may actually offer some health benefits. Some studies have noted that coffee may be associated with a decrease in mortality and have some protective value against a variety of diseases including:

  • Parkinson's disease . A 2010 review study found that higher regular consumption of caffeine was correlated with a lower risk of Parkinson's. A 2020 study in the Journal Neurology looked at whether coffee can protect people with a specific gene mutation that decreases risk of developing Parkinson's and found a correlation between that genetic mutation and blood caffeine levels.
  • Type 2 diabetes . Though some research indicates that caffeine can raise blood sugar and insulin levels for people with diabetes, if you don't yet have the disease, being a regular coffee drinker could actually lower your risk of developing it. A large 2014 study found that people who increased coffee consumption by more than one cup per day saw an 11% lower risk of developing Type 2 diabetes.
  • Liver disease . According to a 2017 study , coffee has "hepatoprotective properties," meaning it can help protect the liver. That investigation found that coffee appears to reduce the risk of liver cancer and may slow the progression of chronic liver diseases.
  • Heart failure. The American Heart Association reports that drinking one or more cups of coffee per day may reduce the risk of heart failure, but only if the coffee contains caffeine. That's according to a 2021 study looking at the connection between heart health and coffee intake.
  • Stroke . Coffee consumption and risk of stroke have been studied extensively, and results have been mixed. However, a 2018 review study found moderate consumption of coffee was protective against stroke, and a large cohort study that followed 83,000 women over 24 years found significant evidence of coffee decreasing stroke risk.

There's also some research that suggests caffeine could help delay the onset of Alzheimer's disease and other types of dementia . In addition, the stimulant effect of caffeine may help support your metabolism, leading to weight loss .

While caffeine certainly has some potential health benefits, it may be that the real value comes from the context of consuming moderate levels of it in coffee or tea rather than just the caffeine itself. There are other elements in coffee and tea that can also impact your overall well-being, and it could be a case of the sum being greater than its parts.

"Health benefits achieved through coffee or tea consumption are generally attributed to the polyphenols and antioxidants," plant-based compounds that can support cellular health that are present in the beverages, Cooper says.

Negative Health Effects of Caffeine

Caffeine dependency is a real thing, and if you're used to consuming a certain amount of caffeine on a regular basis and suddenly stop, you'll likely experience withdrawal symptoms including headaches , insomnia, irritability and tiredness . This means that if you're a regular coffee drinker, you can experience negative withdrawal effects if you suddenly start drinking less coffee.

At the other end of the spectrum, too much caffeine can be even more problematic. Excessive consumption can lead to:

  • Anxiousness .
  • Rapid heart rate.
  • Acid reflux or upset stomach.

The U.S. Food and Drug Administration notes that rapid consumption of high levels of caffeine – on the order of 1,200 milligrams per day – could lead to seizures. And Cooper notes that if you consume 10 grams (or 10,000 milligrams) of caffeine – equivalent to what would be found in about 100 cups of coffee – that amount of caffeine can be fatal. A typical 8-ounce cup of drip-brewed coffee contains 100 milligrams of caffeine. "These toxic levels are usually achieved with caffeine powders or pills." Tolliver adds that if you're going to use a concentrated form of caffeine, be very careful. "Powder and liquid forms of caffeine can be very concentrated and should be used cautiously – or not at all." For example, "one teaspoon of pure powdered caffeine is equivalent to 28 cups of coffee. A half cup of liquid concentrated caffeine is equivalent to 20 cups of coffee. Consumption of caffeine at this level could lead to death."

How Much Caffeine Is Safe?

Given the wide range of impacts caffeine can have on your health, you're likely wondering how much is safe and what's the optimal amount to consume daily. The FDA recommends that healthy adults consume no more than 400 milligrams of caffeine per day. "That's about four cups of brewed coffee, 10 cans of soda or two energy drinks," Tolliver says.

But there are some caveats. "People with hypertension should be cautious because caffeine can elevate blood pressure," Tolliver notes. There has also been some concern about caffeine consumption among pregnant women. The American College of Obstetricians and Gynecologists notes that pregnant women can safely consume up to 200 milligrams of caffeine per day, which is what's found in about two cups of coffee.

And kids should steer clear of caffeine, especially in the form of high-sugar energy drinks that can pack a lot more caffeine than the average cup of coffee. No safe limits of caffeine have been established for children, and the American Academy of Pediatrics recommends that children not consume caffeine because they may be more susceptible to caffeine's effects.

There's also concern about bone health in kids whose bodies are still growing and developing. Some research has shown that caffeine consumption increases calcium excretion from the body, and thus the concern is that lost calcium could inhibit bone formation.

For the majority of people, moderation is the key. "Caffeine still has some risks, however drinking a daily cup of coffee is likely fine to do," Tolliver says.

What to Do if You've Had Too Much

"Coffee is a beloved morning routine for millions of people around the globe," Tolliver says, but it's best to "remember to enjoy in moderation." Some experts say that caffeine can have a diuretic effect in some situations, so it’s best to always hydrate with plain water and keep your caffeine intake at a moderate.

If you’ve consumed too much caffeine, know that it'll take a little while for your system to process it all, Cooper notes. "Caffeine is metabolized differently by individuals based on genetics, health conditions and medications. Caffeine has a half-life of 2 ½ to 4 ½ hours, meaning every 2 ½ to 4 ½ hours the amount of caffeine is reduced to half of the original amount."

That said, if you know you've ingested a dangerous level of caffeine or have severe symptoms, contact your local poison control center or your medical provider immediately.

If your heart is racing or you're feeling jittery, Tolliver recommends "practicing some mindful breathing exercises and going for some physical activity with a walk or bike ride."

Foods, Beverages That May Promote Calm

Senior woman standing in her kitchen. She is putting the kettle on while looking at the camera.

The U.S. News Health team delivers accurate information about health, nutrition and fitness, as well as in-depth medical condition guides. All of our stories rely on multiple, independent sources and experts in the field, such as medical doctors and licensed nutritionists. To learn more about how we keep our content accurate and trustworthy, read our  editorial guidelines .

Cooper is a registered dietitian for prevention and wellness services at Orlando Health in Florida.

Tolliver is clinical assistant professor of family medicine at the Ohio State University Wexner Medical Center in Columbus.

Tags: caffeine , diet and nutrition , food and drink

Most Popular

buffalo case study caffeine

health disclaimer »

Disclaimer and a note about your health », you may also like, best diets for women over 50.

Janet Helm Feb. 16, 2024

buffalo case study caffeine

7 Easy Keto Desserts Everyone Will Love

Elaine K. Howley and Ruben Castaneda Feb. 9, 2024

buffalo case study caffeine

Grocery List for Athletes

Annika Urban Feb. 9, 2024

buffalo case study caffeine

Sugar Fee and No Sugar Snacks

Julie Upton Feb. 8, 2024

buffalo case study caffeine

What Is the Dr. Now Diet?

Katie Bourque and Claire Wolters Feb. 6, 2024

Keto Diet Pills: Do They Really Work?

Elaine K. Howley and Shanley Chien Feb. 1, 2024

buffalo case study caffeine

Yams vs. Sweet Potatoes

Toby Amidor Jan. 31, 2024

buffalo case study caffeine

Best Diets for Seniors

Lisa Esposito and Elaine K. Howley Jan. 31, 2024

buffalo case study caffeine

Gluten-Free Buckwheat Recipes

Kelly LeBlanc Jan. 31, 2024

buffalo case study caffeine

Best Foods for Gut Health

Ruben Castaneda and Elaine K. Howley Jan. 29, 2024

buffalo case study caffeine

Appointments at Mayo Clinic

  • Nutrition and healthy eating

The Mayo Clinic Diet: What is your weight-loss goal? 5-10 lbs, 11-25 lbs, or 25+ lbs

Caffeine: How much is too much?

Caffeine has its perks, but it can pose problems too. Find out how much is too much and if you need to curb your consumption.

If you rely on caffeine to wake you up and keep you going, you aren't alone. Millions of people rely on caffeine every day to stay alert and improve concentration.

How much is too much?

Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks.

Caffeine in powder or liquid form can provide toxic levels of caffeine, the U.S. Food and Drug Administration has cautioned. Just one teaspoon of powdered caffeine is equivalent to about 28 cups of coffee. Such high levels of caffeine can cause serious health problems and possibly death.

Although caffeine use may be safe for adults, it's not a good idea for children. Adolescents and young adults need to be cautioned about excessive caffeine intake and mixing caffeine with alcohol and other drugs.

Women who are pregnant or who are trying to become pregnant and those who are breast-feeding should talk with their doctors about limiting caffeine use to less than 200 mg daily.

Even among adults, heavy caffeine use can cause unpleasant side effects. And caffeine may not be a good choice for people who are highly sensitive to its effects or who take certain medications.

Read on to see if you may need to curb your caffeine routine.

You drink more than 4 cups of coffee a day

You may want to cut back if you're drinking more than 4 cups of caffeinated coffee a day (or the equivalent) and you have side effects such as:

  • Nervousness
  • Irritability
  • Frequent urination or inability to control urination
  • Fast heartbeat
  • Muscle tremors

Even a little makes you jittery

Some people are more sensitive to caffeine than are others. If you're susceptible to the effects of caffeine, even small amounts may prompt unwanted effects, such as restlessness and sleep problems.

How you react to caffeine may be determined in part by how much caffeine you're used to drinking. People who don't regularly drink caffeine tend to be more sensitive to its effects.

You're not getting enough sleep

Caffeine, even in the afternoon, can interfere with your sleep. Even small amounts of sleep loss can add up and disturb your daytime alertness and performance.

Using caffeine to mask sleep deprivation can create an unwelcome cycle. For example, you may drink caffeinated beverages because you have trouble staying awake during the day. But the caffeine keeps you from falling asleep at night, shortening the length of time you sleep.

You're taking medications or supplements

Some medications and herbal supplements may interact with caffeine. Examples include:

  • Ephedrine. Mixing caffeine with this medication — which is used in decongestants — might increase your risk of high blood pressure, heart attack, stroke or seizure.
  • Theophylline. This medication, used to open up bronchial airways, tends to have some caffeine-like effects. So taking it with caffeine might increase the adverse effects of caffeine, such as nausea and heart palpitations.
  • Echinacea. This herbal supplement, which is sometimes used to prevent colds or other infections, may increase the concentration of caffeine in your blood and may increase caffeine's unpleasant effects.

Talk to your doctor or pharmacist about whether caffeine might affect your medications.

Curbing your caffeine habit

Whether it's for one of the reasons above or because you want to trim your spending on coffee drinks, cutting back on caffeine can be challenging. An abrupt decrease in caffeine may cause withdrawal symptoms, such as headaches, fatigue, irritability and difficulty focusing on tasks. Fortunately, these symptoms are usually mild and get better after a few days.

To change your caffeine habit, try these tips:

  • Keep tabs. Start paying attention to how much caffeine you're getting from foods and beverages, including energy drinks. Read labels carefully. But remember that your estimate may be a little low because some foods or drinks that contain caffeine don't list it.
  • Cut back gradually. For example, drink one fewer can of soda or drink a smaller cup of coffee each day. Or avoid drinking caffeinated beverages late in the day. This will help your body get used to the lower levels of caffeine and lessen potential withdrawal effects.
  • Go decaf. Most decaffeinated beverages look and taste much the same as their caffeinated counterparts.
  • Shorten the brew time or go herbal. When making tea, brew it for less time. This cuts down on its caffeine content. Or choose herbal teas that don't have caffeine.
  • Check the bottle. Some over-the-counter pain relievers contain caffeine. Look for caffeine-free pain relievers instead.

The bottom line

If you're like most adults, caffeine is a part of your daily routine. Usually, it won't pose a health problem. But be mindful of caffeine's possible side effects and be ready to cut back if necessary.

There is a problem with information submitted for this request. Review/update the information highlighted below and resubmit the form.

From Mayo Clinic to your inbox

Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Click here for an email preview.

Error Email field is required

Error Include a valid email address

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

Thank you for subscribing!

You'll soon start receiving the latest Mayo Clinic health information you requested in your inbox.

Sorry something went wrong with your subscription

Please, try again in a couple of minutes

  • Lieberman HR, et al. Daily patterns of caffeine intake and the association of intake with multiple sociodemographic and lifestyle factors in U.S. adults based on the NHANES 2007-2012 surveys. Journal of the American Academy of Nutrition and Dietetics. 2019; doi:10.1016/j.jand.2018.08.152.
  • 2015-2020 Dietary Guidelines for Americans. U.S. Department of Health and Human Services and U.S. Department of Agriculture. https://health.gov/our-work/food-nutrition/2015-2020-dietary-guidelines/guidelines. Accessed Feb. 1, 2020.
  • Spilling the beans: How much caffeine is too much. U.S. Food and Drug Administration. https://www.fda.gov/consumers/consumer-updates/spilling-beans-how-much-caffeine-too-much. Accessed Sept. 20, 2019.
  • Duyff RL. Think your drinks. In: Academy of Nutrition and Dietetics Complete Food and Nutrition Guide. 5th ed. Houghton Mifflin Harcourt; 2017.
  • Bordeaux B. Benefits and risks of caffeine and caffeinated beverages. https://www.uptodate.com/contents/search. Accessed Sept. 20, 2019.
  • Pure and highly concentrated caffeine. U.S. Food and Drug Administration. https://www.fda.gov/food/dietary-supplement-products-ingredients/pure-and-highly-concentrated-caffeine. Accessed Sept. 20, 2019.
  • Caffeine. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Feb. 7, 2020.

Products and Services

  • Available Health Products from Mayo Clinic Store
  • A Book: Mayo Clinic on High Blood Pressure
  • A Book: Mayo Clinic Family Health Book, 5th Edition
  • The Mayo Clinic Diet Online
  • A Book: Live Younger Longer
  • A Book: The Mayo Clinic Diet Bundle
  • A Book: Mayo Clinic Book of Home Remedies
  • A Book: Cook Smart, Eat Well
  • Newsletter: Mayo Clinic Health Letter — Digital Edition
  • A Book: Mayo Clinic on Digestive Health
  • Alcohol use
  • Alkaline water
  • Artificial sweeteners and other sugar substitutes
  • Autism spectrum disorder and digestive symptoms
  • Breastfeeding nutrition: Tips for moms
  • Is caffeine dehydrating?
  • Calorie calculator
  • Can whole-grain foods lower blood pressure?
  • Carbohydrates
  • Chart of high-fiber foods
  • Cholesterol: Top foods to improve your numbers
  • Coconut water: Is it super hydrating?
  • Coffee and health
  • Diet soda: How much is too much?
  • Dietary fats
  • Dietary fiber
  • Prickly pear cactus
  • Does soy really affect breast cancer risk?
  • Don't get tricked by these 3 heart-health myths
  • High-protein diets
  • How to track saturated fat
  • Is there a special diet for Crohn's disease?
  • Monosodium glutamate (MSG)
  • Nuts and your heart: Eating nuts for heart health
  • Omega-3 in fish
  • Omega-6 fatty acids
  • Phenylalanine
  • Portion control
  • Health foods
  • Planning healthy meals
  • Taurine in energy drinks
  • Underweight: Add pounds healthfully
  • Daily water requirement

Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.

  • Opportunities

Mayo Clinic Press

Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press .

  • Mayo Clinic on Incontinence - Mayo Clinic Press Mayo Clinic on Incontinence
  • The Essential Diabetes Book - Mayo Clinic Press The Essential Diabetes Book
  • Mayo Clinic on Hearing and Balance - Mayo Clinic Press Mayo Clinic on Hearing and Balance
  • FREE Mayo Clinic Diet Assessment - Mayo Clinic Press FREE Mayo Clinic Diet Assessment
  • Mayo Clinic Health Letter - FREE book - Mayo Clinic Press Mayo Clinic Health Letter - FREE book
  • Healthy Lifestyle
  • Caffeine How much is too much

Show the heart some love!

Help us advance cardiovascular medicine.

buffalo case study caffeine

  • The Star ePaper
  • Subscriptions
  • Manage Profile
  • Change Password
  • Manage Logins
  • Manage Subscription
  • Transaction History
  • Manage Billing Info
  • Manage For You
  • Manage Bookmarks
  • Package & Pricing

Did you know there’s caffeine in other items that are not coffee or tea?

Sunday, 11 Feb 2024

Related News

Funding from France beefs up efforts to improve nutrition in Saravan

Funding from France beefs up efforts to improve nutrition in Saravan

School meals to improve nutrition, education outcomes in 103 schools in laos' savannakhet, laos to work with world body to improve nutrition.

While most adults can safely consume 400 mg of caffeine – or about four cups of brewed coffee – a day without any side effects, it’s not just about keeping track of your coffee consumption as other edible items can also contain caffeine. — TNS

You probably know that tea and coffee contain caffeine, but did you know that it can also be found in other drinks, food and some medications?

When it comes to caffeine consumption, you’re not alone if you depend on it to help you concentrate or be alert.

Studies have shown that about 90% of American adults consume a form of caffeine every day.

Caffeine content in beverages widely varies.

Even if you reach for different types of beverages throughout the day, you may be drinking more caffeine than you realise.

With a cup of coffee or tea with breakfast, a soft drink in the afternoon and a piece of chocolate after supper, caffeine may be a significant part of your daily diet.

Some of the most common sources of caffeine are:

  • Soft drinks

Caffeine can also hide under some names that are less recognisable.

Energy drinks have additives that contain caffeine to enhance the effects of the drink.

Knowing about these additives can help you avoid consuming more caffeine than you intend to, so be sure to check labels before you buy.

Some common additives that contain caffeine include:

  • Glucuronolactone
  • Maltodextrin
  • Pantothenic acid
  • Yerba mate.

Caffeine in powder or liquid form can be particularly dangerous.

The US Food and Drug Administration (FDA) has warned that high levels of caffeine can cause serious health problems.

One teaspoon of powdered caffeine is the same as drinking 28 cups of coffee, which is significantly more than the recommended level.

Too much caffeine can cause side effects such as:

  • Fast heartbeat
  • High blood pressure
  • Muscle tremors.

For most adults however, consuming up to 400 milligrammes of caffeine daily does not have adverse side effects.

Depending on the type of beverage, that can be roughly four cups of brewed coffee, 10 cans of cola or two energy shot drinks.

Adolescents and young adults on the other hand, must be cautious when drinking caffeine, and children should avoid it altogether.

People who are sensitive to caffeine’s effects or take certain medications should avoid consuming too much caffeine.

People who are pregnant, want to become pregnant or are breastfeeding should talk with their healthcare team about caffeine consumption.

If caffeine becomes more of a hindrance than a help, you may want to consider cutting back.

This can be challenging because an abrupt decrease can cause withdrawal symptoms like headaches, fatigue and difficulty focusing.

To lessen caffeine withdrawal symptoms, try these tips:

  • Be aware of and track how much caffeine you consume throughout the day.
  • Cut back gradually so your body gets used to lower levels of caffeine.
  • Check products you use for caffeine, such as over-the-counter pain relievers.
  • Shorten the brew time of tea to cut down on the caffeine content, or choose an herbal tea that doesn’t have caffeine.
  • Switch to decaffeinated beverages, which have a similar taste, but much less caffeine than their full-strength counterparts.

Contact your primary care provider for guidance or evaluation if you’re struggling with persistent or severe caffeine withdrawal symptoms. – By Brian Burroughs/Mayo Clinic News Network/Tribune News Service

Brian Burroughs is a family medicine physician assistant with a special interest in headache treatment in Minnesota, United States.

Related stories:

Tags / Keywords: Caffeine , coffee

Found a mistake in this article?

Report it to us.

Thank you for your report!

School meals to improve nutrition, education outcomes in 103 schools in Laos' Savannakhet


Next in health.

buffalo case study caffeine

Trending in Lifestyle

Air pollutant index, highest api readings, select state and location to view the latest api reading.

  • Select Location

Source: Department of Environment, Malaysia

Others Also Read

Best viewed on Chrome browsers.

buffalo case study caffeine

We would love to keep you posted on the latest promotion. Kindly fill the form below

Thank you for downloading.

We hope you enjoy this feature!

To revisit this article, visit My Profile, then   View saved stories .

To revisit this article, select My Account, then   View saved stories

  • Conditionally
  • Newsletter Signup

7 Benefits of Quitting Caffeine That Make It Worth the Struggle

By Ayana Underwood

Medically reviewed by Mathew Devine, DO

An image of a cup of black coffee against a bright yellow background.

All products featured on SELF are independently selected by our editors. However, when you buy something through our retail links, we may earn an affiliate commission.

If you slam a double espresso before work, order a latte as soon as you get to the office, have a soda with lunch, and sip an energy drink as your preworkout—you likely feel wired. You’re not alone in your love of a cup of joe. According to a 2023 study published in European Review for Medical and Pharmacological Sciences , between 80% and 90% of US adults and children have caffeine on a regular basis. 1

Still, you’re probably well aware of how bad too much caffeine can make you feel. As SELF previously reported , caffeine can make you jittery and screw with your stomach (the coffee poops are real!). Your sleep schedule might be kind of shitty too. 2

You might have reached a point where you’re ready to quit caffeine or, at the very least, cut back on the amount of caffeine you drink. The degree to which you feel better if you quit caffeine depends on how much you’re drinking to begin with, Rachel O’Connor, RD, CDN , an oncology dietician at NewYork-Presbyterian, tells SELF. If you’re consuming over 400 mg of caffeine (about four cups of coffee or two energy shots drinks) per day, that’s considered heavy caffeine use, says O’Connor.

Here are some of the health benefits that you could see if you quit caffeine—some of which you might not have even thought about.

FYI: Before you reap the perks of drinking less coffee, you might feel some gnarly caffeine withdrawal symptoms.

Because caffeine use is pretty common, people might forget that it’s still a drug (a stimulant), and it’s possible to become dependent on it. 3 (That often looks like multiple attempts to ditch caffeine without success. 4 )

“When regular caffeine consumers stop [ingesting it], they often experience withdrawal symptoms for three to seven days,” Jennifer Temple, PhD , a director and researcher at the University at Buffalo specializing in caffeine studies, tells SELF. 3

Common withdrawal symptoms include fatigue, headaches, and low energy, says Dr. Temple. 3 According to O’Connor, withdrawal symptoms will likely start between 12 and 24 hours after you quit 3 Whether you quit cold turkey or wean yourself off caffeine, grab some OTC headache relief medication. 3 Staying hydrated and getting enough rest can make withdrawal symptoms easier to handle too. 3

Seven benefits of quitting caffeine

As you know, caffeine likes to steal your sleep—it can shave about 45 minutes off of your time in dreamland. 5,6 If you don’t sleep enough, you might compensate the next day by downing some espresso—which creates a vicious cycle of crappy sleep followed by caffeine use, per a 2023 review published in Sleep Medicine Reviews . 6 As SELF previously reported , caffeine can stay in your system for hours, so it’s possible to feel the stimulating effects well into the night.

Some signs caffeine is wrecking your sleep include trouble falling asleep (of course), headaches, nausea, and feelings of nervousness. So if you give up caffeine, you could end up getting much better rest, says Dr. Temple. (People with insomnia might find this to be especially helpful, per the Sleep Foundation .)

It’s worth noting that quitting might not feel so great at first. “Someone’s energy levels will drop when they quit caffeine, at least initially,” says O’Connor, so you might feel daytime drowsiness or sluggishness. It’s hard to say if your energy levels will go back to where they were before you started consuming coffee, but if you tend to drink coffee later in the day and decide to quit, you might simply have more energy because you’re getting more sleep at night, as O’Connor explains.

If your sleep schedule seems to be off after quitting (which it might be for a few days or, sometimes, a few weeks), try to wake up at the same time each day to get yourself on a more consistent track. Trouble falling asleep? Try a guided meditation or some simple pre-bedtime tricks for a more restful night.

Caffeine can majorly contribute to daily or chronic headaches. It might also trigger migraine in people who are prone to them, according to the American Migraine Foundation . If you struggle with those, you might think going cold turkey will ease your discomfort—but that’s not always true, thanks to caffeine withdrawal, according to O’Connor. This could look like low energy, difficulty concentrating, irritability, and worsening headaches. Because caffeine narrows blood vessels around the brain, “a sudden lack of caffeine, especially when you’re drinking it daily or drinking a lot of it, can trigger a cascade of events that leads to dilated blood vessels which contribute to the headache,” says O’Connor.

In other words, your headaches will likely get worse before they get better. Gradually decreasing your caffeine intake over a week or two, rather than quitting cold turkey, “could help limit some of that severity,” O’Connor says—you could try slowly swapping your regular coffee for decaf.

Caffeine might not be the best thing for your mental health: It stimulates the nervous system and can cause anxiety, and people diagnosed with panic disorders are especially vulnerable to feeling on edge following caffeine use. 7,8,9

“Some people might have anxiety at baseline that’s exacerbated by caffeine, especially when it’s had in excess,” says O’Connor. For those people, she says that caffeine use might cause muscle tremors, a fast heart rate, and nervousness, which can work to make you feel even more anxious.

If you feel jittery after a Dr. Pepper (or three), you might find some relief if you kick the habit, says O’Connor—who also clarifies that how anxious caffeine makes you is different for everyone, so even if your habit is lighter or heavier, individual results here will vary.

Coffee poops are a real pain (literally) in the butt. Caffeine stimulates muscle contractions and gut motility in the body, which makes you go number two, says O’Connor: “If someone is really relying on their cup of coffee for a bowel movement, they might notice that they don’t use the bathroom as quickly in the morning [after quitting].”

I’m a Neurologist. Here’s the One Thing I Do Every Day for My Long-Term Brain Health

By Jenny McCoy, C.P.T.

15 Simple Stretches for Your Tight, Achy Back

By Amy Marturana Winderl, C.P.T.

You might be dealing with a bit of constipation when you first quit. To get things flowing, O’Connor suggests switching to hot water because hot drinks can help smooth muscle relaxation and help out with your bowel movements. You can also try upping your fiber at breakfast. Oatmeal and bananas are good fiber-rich options !

If you have gastroesophageal reflux disease ( GERD ), which coffee can exacerbate, then you know it’s absolutely no fun. “Certain things may trigger reflux in one person and not in someone else. If caffeine is a known [GERD] trigger for someone, cutting back on it will, of course, be helpful,” says O’Connor.

Keep in mind that your acid reflux might not be caused by caffeine. To figure out if caffeine is really the issue, O’Connor suggests eliminating coffee (or however you get your fix) for a week to see if you feel different. If caffeine is, in fact, causing GERD symptoms, remember that the extent of the relief you’ll experience from GERD symptoms after quitting caffeine is individualized, according to O’Connor.

Caffeine is a diuretic. Not only does that mean caffeine makes you pee more, but it also dries out your mouth, Chrystle Cu, DDS , a dentist at Young Dental Group in California and founder of Cocofloss , tells SELF. Dry mouth (meaning you don’t have enough saliva to keep your mouth moist) isn’t great for your oral health . Saliva not only contains minerals that prevent tooth decay, but it also helps to wash away leftover food from the teeth and gum line—and makes swallowing easier. Too little saliva can cause “an imbalance of the oral microbiome,” says Dr. Cu. 10 “Reducing one’s caffeine intake would help in reducing one’s dry mouth, which will translate into a healthier mouth overall.”

If you’re worried about coffee stains, scheduling a routine dental cleaning can help lift some of them from your tooth enamel. 11 You can also give whitening toothpaste a shot.

Without your daily dose of caffeine, your mornings might look a little different. That’s not a bad thing: There are a ton of non-caffeinated beverages that you can give a whirl, many of which can feel like a special treat.

See what sparks the most joy: You can try caffeine-free herbal teas, which come in a number of delicious flavors, like Glazed Lemon Loaf , Calm Chamomile , and Organic Baked Cinnamon Apple . Now is your moment to up your smoothie game, too! Fruit “will provide an easily digestible source of carbohydrates to give you a boost of energy,” O’Connor says. Yogurt can help stabilize your blood sugar to help make sure that energy lasts throughout your whole morning. If you’re a soda lover, consider swapping your Sprite for seltzer.

You might be ready to retire your Mr. Coffee or 86 yourself from your favorite coffee shop ASAP, but let’s be very real: Quitting caffeine is hard! Cut yourself some slack if you’re struggling. You can always give it another shot—just maybe not one of espresso.

  • So, Is Coffee Bad for You in Any Way?
  • Why Starbucks’s New Olive Oil Coffee Is Allegedly Making People Poop a Whole Lot
  • So, What’s the Latest I Can Pound Coffee and Still Sleep Like a Baby?
  • European Review for Medical and Pharmacological Sciences, Caffeine Addiction and Determinants of Caffeine Consumption Among Health Care Providers: A Descriptive National Study
  • Journal of Biological Rhythms , Regular Caffeine Intake Delays REM Sleep Promotion and Attenuates Sleep Quality in Healthy Men
  • StatPearls , Caffeine Withdrawal
  • Journal of Caffeine and Adenosine Research, Prevalence and Correlates of Caffeine Use Disorder Symptoms Among a United States Sample
  • Risk Management and Healthcare Policy, Effects of Caffeine on Sleep Quality and Daytime Functioning
  • Sleep Medicine Reviews , The Effect of Caffeine on Subsequent Sleep: A Systematic Review and Meta-Analysis
  • Psychiatry Research , The Association Between Coffee Consumption and Risk of Incident Depression and Anxiety: Exploring the Benefits of Moderate Intake
  • Cureus, The Neurophysiology of Caffeine as a Central Nervous System Stimulant and the Resultant Effects on Cognitive Function
  • General Hospital Psychiatry, Effects of Caffeine on Anxiety and Panic Attacks in Patients With Panic Disorder: A Systematic Review and Meta-Analysis
  • The Public Library of Science One , Dysbiotic Salivary Microbiota in Dry Mouth and Primary Sjögren’s Syndrome Patients
  • Dentistry Journal , A Critical Review of Modern Concepts for Teeth Whitening

buffalo case study caffeine

SELF does not provide medical advice, diagnosis, or treatment. Any information published on this website or by this brand is not intended as a substitute for medical advice, and you should not take any action before consulting with a healthcare professional.

I Was Diagnosed With Colon Cancer at 32. Here Are the First Symptoms I Had.

Read the Latest on Page Six

  • Weird But True
  • Sex & Relationships
  • Viral Trends
  • Human Interest
  • Fashion & Beauty
  • Food & Drink

trending now in Lifestyle

I'm a certified personal trainer — here is the No. 1 best exercise for weight loss, no gym time required

I'm a certified personal trainer — here is the No. 1 best...

I'm a trailer park mom living on $30K a year — here's how I feed my family of four for less than $250 a week

I'm a trailer park mom living on $30K a year — here's how I...

Long COVID can destroy your ability to exercise or do simple tasks — now we may know why

Long COVID can destroy your ability to exercise or do simple...

Customer shocks restaurant staff by leaving $10,000 tip — then they found out the heartbreaking reason why

Customer shocks restaurant staff by leaving $10,000 tip — then...

Couple who traveled to all 63 US national parks reveals which one is the 'best'

Couple who traveled to all 63 US national parks reveals which one...

Gen Z is bringing back landline phones because they think they look 'cool': 'I love to twirl the cord'

Gen Z is bringing back landline phones because they think they...

Ex-McDonald's chef reveals if fan-favorite item is actually shrinking

Ex-McDonald's chef reveals if fan-favorite item is actually...

I was love-bombed on Hinge by Tesla-driving realtor — then he swindled me out of my life savings

I was love-bombed on Hinge by Tesla-driving realtor — then he...

This secret ingredient could prolong the effects of caffeine, scientist says.

  • View Author Archive
  • Follow on Twitter
  • Get author RSS feed

Thanks for contacting us. We've received your submission.

Want that long-lasting buzz from your morning coffee? Skip that second cup and try this surprising breakfast addition instead.

Eating grapefruit with your java could potentially extend the effects of the caffeine and ward off that unwanted afternoon slump, according to Michelle Francl, a chemistry professor at Bryn Mawr College.

“If you eat a lot of grapefruit you can increase the time the caffeine remains in the system,” she said during a Chemistry World webinar this week, adding that cabbage, broccoli and brussels sprouts could help caffeine clear from your system quicker.

Now, don’t go throwing grapefruit into your cup of joe — just eating the fruit or drinking juice alongside your morning coffee could prolong the caffeine high, according to some experts.

But while past studies have investigated claims that this is due to naringin, responsible for grapefruit’s bitter taste, researchers have reported that it may not alter caffeine metabolism .

Iced tea with lemon and grapefruit on wooden background.

Last month, Francl enraged tea purists by suggesting that adding a pinch of salt to a cup of tea makes it “better.”

Published in her book “ Steeped: The Chemistry of Tea ,” the chemist offered research-backed methods to making the perfect brews and flavor profiles, saying that “the sodium ions in salt block the bitter receptors in our mouths,” per the Associated Press .

But her suggestion was met with criticism from salty Brits, who said it “ feels like a crime .” Even the US Embassy weighed in, posting a statement to X regarding the rift that landed Americans in “hot water.”

They ensured that “the unthinkable notion of adding salt to Britain’s national drink is not official United States policy. And never will be,” the letter read.

“The US embassy will continue to make tea in the proper way – by microwaving it,” they quipped.

A woman holding a glass of liquid for making the best cup of tea, as shared by Michelle Francl, the Frank B. Mallory Professor of Chemistry.

While Francl assumed there would be “interest” in the topic, she never imagined it would lead to “a diplomatic conversation with the US Embassy,” she told the AP, pondering the coffee versus tea debate between the two nations.

“I wonder if we’re just a more caffeinated society — coffee is higher in caffeine,” she mused. “Or maybe we’re just trying to rebel against our parent country.”

Share this article:

Iced tea with lemon and grapefruit on wooden background.


buffalo case study caffeine

Can I hire someone to write essay?

Student life is associated with great stress and nervous breakdowns, so young guys and girls urgently need outside help. There are sites that take all the responsibility for themselves. You can turn to such companies for help and they will do all the work while clients relax and enjoy a carefree life.

Take the choice of such sites very seriously, because now you can meet scammers and low-skilled workers.

On our website, polite managers will advise you on all the details of cooperation and sign an agreement so that you are confident in the agency. In this case, the user is the boss who hires the employee to delegate responsibilities and devote themselves to more important tasks. You can correct the work of the writer at all stages, observe that all special wishes are implemented and give advice. You pay for the work only if you liked the essay and passed the plagiarism check.

We will be happy to help you complete a task of any complexity and volume, we will listen to special requirements and make sure that you will be the best student in your group.

Finished Papers

Know Us Better

  • Knowledge Base
  • Referencing Styles
  • Know Our Consultance
  • Revision and Refund Policy
  • Terms Of Use

Johan Wideroos

Writing my essay with the top-notch writers!

The writers you are supposed to hire for your cheap essay writer service are accomplished writers. First of all, all of them are highly skilled professionals and have higher academic degrees like Masters and PhDs. Secondly, all the writers have work experience of more than 5 years in this domain of academic writing. They are responsible for

  • Omitting any sign of plagiarism
  • Formatting the draft
  • Delivering order before the allocated deadline

Advanced essay writer

Eloise Braun

Customer Reviews

Emery Evans

Finished Papers

  • Our Listings
  • Our Rentals
  • Testimonials
  • Tenant Portal

buffalo case study caffeine

Looking for something more advanced and urgent? Then opt-in for an advanced essay writer who’ll bring in more depth to your research and be able to fulfill the task within a limited period of time. In college, there are always assignments that are a bit more complicated and time-taking, even when it’s a common essay. Also, in search for an above-average essay writing quality, more means better, whereas content brought by a native English speaker is always a smarter choice. So, if your budget affords, go for one of the top 30 writers on our platform. The writing quality and finesse won’t disappoint you!

Premium essay writers

Essay writing help from a premium expert is something everyone has to try! It won’t be cheap but money isn’t the reason why students in the U.S. seek the services of premium writers. The main reason is that the writing quality premium writers produce is figuratively out of this world. An admission essay, for example, from a premium writer will definitely get you into any college despite the toughness of the competition. Coursework, for example, written by premium essay writers will help you secure a positive course grade and foster your GPA.

essays service custom writing company

Dr.Jeffrey (PhD)

U.S. flag

An official website of the United States government

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

  • Publications
  • Account settings
  • Advanced Search
  • Journal List

Logo of nutrients

Coffee and Caffeine Consumption for Human Health

Raquel abalo.

1 Department of Basic Health Sciences, Faculty of Health Sciences, University Rey Juan Carlos (URJC), 28922 Alcorcón, Spain; [email protected] ; Tel.: +34-91-488-8854

2 High Performance Research Group in Physiopathology and Pharmacology of the Digestive System (NeuGut-URJC), URJC, 28922 Alcorcón, Spain

3 Associated I+D+i Unit to the Institute of Medicinal Chemistry (IQM), Scientific Research Superior Council (CSIC), 28006 Madrid, Spain

4 Working Group of Basic Sciences in Pain and Analgesia of the Spanish Pain Society (Grupo de Trabajo de Ciencias Básicas en Dolor y Analgesia de la Sociedad Española del Dolor), 28046 Madrid, Spain

Coffee is one of the most popular and consumed beverages worldwide, and caffeine is its best-known component, present also in many other beverages (tea, soft drinks, energy drinks), foodstuffs (cocoa, chocolate, guarana), sport supplements and even medicines. Besides caffeine, many other components, either beneficial for health (chlorogenic acids, polyphenols, diterpenes, micronutrients, melanoidins, fiber) or not (lipids in unfiltered coffee, or acrylamide resulting from coffee bean roasting), are present in coffee. Just to illustrate the scientific interest of coffee and caffeine, when these terms are combined in PubMed (as “coffee OR caffeine”), almost 50,000 papers can be retrieved (as of 10 August 2021). Furthermore, from 2000 to 2020, the number of manuscripts published per year has more than doubled (from 972 to 2601). Within this context of increasing interest in the topic, the Special Issue (SI) on “Coffee and Caffeine Consumption for Human Health” has collected twenty-one manuscripts (five narrative reviews and sixteen original articles, including two meta-analyses).

Most of the original reports obtained information on coffee or caffeine consumption in humans through dietary surveys or interviews. These studies have the limitation of recall bias. In addition, caffeine content needs to be estimated for most foods from packaging, databases, scientific literature or extrapolated from similar foods, although in some cases it was directly measured from samples of coffee or soft drinks. Rochat et al. found that, in agreement with reports from other high-income countries, coffee is the main source of caffeine consumption in Switzerland, mostly consumed early in the morning (6–9 am), although some differences were found across age groups, smoking status, and linguistic regions [ 1 ]. Cultural differences in coffee/caffeine consumption are important and may contribute to the health effects observed in different geographic regions. Furthermore, coffee/caffeine consumption may be likewise modulated by expectation (placebo) effects and vice versa. Mendes et al. translated, adapted, and validated the Caffeine Expectancy Questionnaire (CaffEQ), originally designed for the American population [ 2 ], to the Brazilian culture (CaffEQ-BR), and confirmed that coffee is the main source of daily caffeine intake in Brazil [ 3 ], the largest coffee producer and exporter in the world market.

Most studies tried to determine whether there is an association between coffee/caffeine intake and different health outcomes. Rodas et al. specifically evaluated the effect of caffeine intake, physical activity levels, and sedentary behavior on the inflammatory status in healthy staff and students at the University of the Balearic Islands (Mallorca, Spain). In this sample, sedentary behavior and body fat accumulation had clear pro-inflammatory effects, whereas regular but relatively low caffeine consumption (whose main source was also coffee) could not be demonstrated to exert robust anti-inflammatory effects [ 4 ]. Antwerpes et al., analyzed the relationship between regular coffee intake and neurocognitive performance in patients coinfected with human immunodeficiency virus and hepatitis C virus, who experience an accelerated aging process and cognitive impairment. The authors showed a positive association between elevated coffee intake (three or more cups per day) and neurocognitive functioning parameters, even after adjusting for liver disease correlates, suggesting that coffee intake may be neuroprotective in these patients [ 5 ]. Likewise, Herden and Weissert studied the effect of coffee and caffeine consumption on patients with multiple sclerosis (MS)-related fatigue. Importantly, the authors showed that coffee intake did not cause severe side effects in MS patients and identified a specific set of patients who might benefit from coffee consumption [ 6 ]. One meta-analysis evaluated the effect of caffeine consumption on the risk and progression of Parkinson’s disease (PD). Individuals consuming caffeine on a regular basis had a significantly lower risk of developing PD during follow-up evaluation, and those that already had the disease and consumed caffeine showed a significantly decelerated PD progression. However, Hong et al. could not determine the optimal daily dosage or food source of caffeine [ 7 ]. According to the review by Jee et al., coffee/caffeine neuroprotective effects seem to be broader and sex- and age-specific. Indeed, they concluded that caffeine consumption reduces the risk of stroke, dementia, and depression in women and that of PD in men. Nevertheless, it may increase sleep disorders and anxiety disorders in adolescence in both men and women. They suggested that caffeine use should be individualized according to sex (and age) in the context of neurologic and psychiatric diseases [ 8 ]. Nowaczewska et al., on the other hand, reviewed the ambiguous role of caffeine in migraine headache. They did not find any scientific evidence showing that a single dose of caffeine may trigger migraine, although it may influence migraines (i.e., through its vasoconstrictor actions during the premonitory symptoms). Chronic caffeine overuse may lead to migraine chronification and sudden caffeine cessation may trigger migraine attacks. Thus, as recommended by the authors, migraine sufferers should avoid caffeine withdrawal headache by keeping a consistent daily intake, not exceeding 200 mg [ 9 ].

Three studies evaluated the relationship of coffee consumption with the risk of metabolic, endocrine, or cardiovascular diseases according to genetic polymorphisms. Using data from the Korean Genome and Epidemiology Study (KGES), Jin et al. identified five single nucleotide polymorphisms (SNPs) related with habitual coffee consumption in this Korean population and showed the lowest risk of prediabetes and type 2 diabetes among black-coffee consumers with minor alleles of these SNPs compared with those with major alleles [ 10 ]. Using data from KGES too, Han et al. found that subsets of genetic variants in the adenosine receptors (involved in caffeine signaling) gene family modulate the effect of coffee intake on dyslipidemia risk in a sex-dependent manner [ 11 ]. In the third study, Liu et al. found that consumption of coffee was significantly associated with a decreased risk of coronary heart disease among Taiwanese adults carrying the GG genotype of TRIB1 (tribbles pseudokinase 1, a gene involved in cholesterol metabolism and atherosclerosis process) [ 12 ]. These three examples of genetic studies strongly suggest that dietary guidelines for coffee intake in the prevention and management of metabolic, endocrine, and cardiovascular disorders should consider the influence of genetic polymorphisms.

The main problem with the survey/interview-based studies is the lack of accurate information regarding type (roasting) or brand of coffee, caffeine content (caffeinated, decaffeinated), methods of preparation (boiled, filtered, brewed), and consumption of other caffeine sources. Thus, quantification of daily consumption of caffeine (and other compounds) is a real challenge in this kind of studies. Moua et al. tried to overcome this limitation by using volume of coffee consumed (not number of cups) in a dose-response meta-analysis of the association between coffee consumption and c-reactive protein, a general biomarker of chronic inflammation. Unfortunately, heterogeneity of study populations (differences in sample size; cultural differences in coffee composition; relevant individual confounders such as age, sex, body mass index, smoking, alcohol intake, diet, activity, comorbidities, etc.) produced inconsistent associations [ 13 ]. Thus, in addition to collecting detailed information on coffee type and preparation method, measuring biomarkers of coffee consumption such as urinary metabolites may be helpful to more precisely determine the amounts of bioactive compounds consumed and their effects. In this sense, Wu and Chen explored the association between urine caffeine metabolites and urine flow rate, using data from the US National Health and Nutrition Examination Survey (NHANES) and metabolomics for urine analyses. The association was positive, with more metabolites showing certain flow-dependency in males compared to females and in young compared to elderly participants [ 14 ]. This factor is important to correctly interpret urinary data regarding caffeine.

Intervention studies allow to establish more robust cause-effect associations. In this SI, two original studies used a double-blind, placebo-controlled crossover design to evaluate the ergogenic effects of caffeine. In 13 males and 17 females, Fuller et al. examined the effects of trait (long-standing pre-disposition) mental and physical energy and fatigue to changes in moods, cognitive and fine-motor task performance. The results suggest that evaluating trait may be a practical, low-cost method to control for interindividual differences in the ergogenic neurocognitive effects of caffeine, without the need for genetic testing [ 15 ]. On the other hand, Wilk et al. demonstrated that a single moderate dose of caffeine (3–6 mg/kg b.m.) increased mean power output and mean bar velocity during an explosive bench press throw in 12 male athletes habituated to caffeine ingestion, meaning that caffeine enhances performance in this context, although the long-term training effects with caffeine need to be determined [ 16 ].

This SI includes three original studies showing new data in animal models using different beverages for different purposes, somehow representative of those also addressed in humans. Ahmad et al. performed a classical toxicity study in rats of the beverage Tongkat ali, widely used in Malaysia, made of coffee infused with the additive Eurycoma longifolia . This study demonstrated a good safety profile for this beverage in male and female rats [ 17 ]. The other rat study, by Velázquez et al., investigated the effects of caffeine alone or as part of a green coffee extract (GCE) in lean female rats with diet-induced hepatic steatosis, as a preclinical model of non-alcoholic fatty liver disease, a highly prevalent condition nowadays, without specific pharmacological treatment. Using different techniques, including lipidomics on liver tissue, the GCE, but not caffeine alone, was found to reduce liver triglyceride levels, through a combination of different molecular mechanisms of action [ 18 ]. Whether longer treatment duration and/or higher doses might be even more effective is unknown. In the last preclinical study, a controlled laboratory trial performed in piglets, Treml et al. showed that a high dose of Red Bull, a popular energy drink among athletes containing caffeine, taurine and glucose among other compounds, increased heart rate at near sea level. However, a high dose of this beverage did not worsen tachycardia during acute short-term hypoxia (simulating high altitude conditions). The authors demonstrated that this beverage significantly increased pulmonary shunt fraction without changing distribution of pulmonary blood flow during hypoxia [ 19 ]. The specific contributions of the different components of this beverage remain to be identified.

Ruta and Farcasanu reviewed the studies evaluating the molecular mechanisms of action of caffeine in Saccharomyces cerevisiae as a simple model of eukaryotic cell. In addition to its three well-known mechanisms, namely intracellular mobilization of calcium, inhibition of phosphodiesterases and antagonism of adenosine receptors, the studies performed in this yeast model have confirmed that the pleiotropic effects of caffeine involve also key molecular mechanisms related with DNA repair mechanisms, cancer, and aging [ 20 ]. In contrast, Kolb et al. reviewed the mechanisms that might contribute to explain the beneficial effects of habitual coffee consumption on health. The authors excluded caffeine content as well as radical scavenging properties, anti-inflammatory activity, and genetic polymorphisms as major contributors to coffee healthy effects. Instead, they propose that the mechanisms involve a combination of factors promoting cell protection, namely upregulation of proteins with antioxidant, detoxifying and repair functions through coffee phenolic phytochemicals, as well as modulation of the gut-microbiota, through the non-digestible components of coffee (prebiotics), although this has been scarcely explored [ 21 ]. Since the gastrointestinal tract is the first body system that gets in contact with ingested coffee, Iriondo-DeHond et al. reviewed the effects produced by coffee and its components on the different constituents of the gut wall (mucosa, muscle layers, enteric nervous system), the different gastrointestinal organs, the gastrointestinal tract as a whole and the brain-gut axis, only to find that the effects of coffee and its derivatives on the health of this axis (that affect not only gastrointestinal motility, permeability and sensitivity but also a complete spectrum of central nervous functions and disorders, from emotions to neurodegeneration) have not been deeply investigated yet [ 22 ].

Altogether, the current view is that coffee/caffeine intake exerts multiple health benefits in humans, at least in specific populations (with a particular genetic profile or suffering from specific diseases), but the specific effects in the different organs and systems, as well as the mechanisms involved are far from clear. Furthermore, within the current context aiming to sustainable development, the coffee plant Coffee sp. and its so-far relatively neglected by-products are expected to become soon a source of ingredients for new functional foods whose properties will need to be precisely determined. We hope the readers of this SI will find inspiration for new studies on the topic.


The author research is funded by the following projects: “Novel Coffee by-Product Beverages for an Optimal Health of the Brain–Gut Axis (COFFEE4BGA)”, by the Ministerio de Ciencia e Innovación (PID2019-111510RB-I00); “N-acetilcisteína frente a la COVID-19 grave y sus secuelas: estudio en un modelo preclínico de pseudoinfección y sepsis (NACfightsCOVID-19)”, funded by URJC-Banco de Santander (2020 call). The author is grateful to all the researchers that submitted their interesting reports to this SI.

This research received no external funding.

Conflicts of Interest

The author declares no conflict of interest.

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Find anything you save across the site in your account

13 Best Caffeine Eye Creams, Reviewed by Dermatologists

buffalo case study caffeine

By Macaela MacKenzie

13 Best Caffeine Eye Creams 2024 Tested by Dermatologists

So you’ve been doing some revenge bedtime procrastination and it shows. We can't fix your sleep deprivation but the best caffeine eye cream can do something about those under eye bags and dark circles. “Caffeine works to reduce puffiness by clamping down on blood vessels, helping to reduce swelling,” Marisa Garshick , MD, FAAD, a board-certified dermatologist in New York and clinical assistant professor of dermatology at Weill Cornell Medicine, tells Glamour .

In other words, the best caffeine eye cream really can work magic. “You can see results fairly quickly, even within an half an hour,” Aya Ahram , DO, FAAD, a board-certified dermatologist at Hudson Dermatology and Laser Surgery in New York, tells Glamour . Over time—about four to six weeks—consistent use of caffeine eye cream can also help reduce the appearance of dark circles (which is why caffeine is often found in the best eye creams for dark circles ), adds Navin S. Arora , DO, FAAD, board-certified dermatologist, founder of Borealis Dermatology in New York, and clinical assistant professor at the NYU Grossman School of Medicine.

Ahead, these are the caffeine eye creams dermatologists have tested and say really work. Plus, as a health and beauty editor with over a decade of experience (and as a mom who knows a thing or two about tired eyes), I'm sharing my reviews as well.

The best caffeine eye creams, at a glance

  • Best overall: Skinceuticals AGE Advanced Eye , $116
  • Best drugstore caffeine eye cream: Neutrogena HydroBoost+ Caffeine Eye Gel Cream , $16
  • Best caffeine eye cream for sensitive skin: CeraVe Skin Renewing Eye Cream
  • Best for dry skin: Colorescience Total Eye Firm and Repair Concentrate , $94
  • Best caffeine eye mask: DRMTLGY Brightening Eye Masks , $44
  • Best caffeine eye cream with vitamin c : Origins GinZing Refreshing Eye Cream , $37

All products featured on Glamour are independently selected by our editors. However, when you buy something through our retail links, we may earn an affiliate commission.

SkinCeuticals AGE Advanced Eye

Best overall: SkinCeuticals A.G.E. Advanced Eye

This do-it-all eye cream is a favorite of both Dr. Arora and Dr. Garshick (who keeps a jar in her personal rotation). “It addresses multiple signs of aging around the eye, including crepiness, crows feet, dark circles and puffiness,” says Dr. Garshick. Caffeine targets puffy eyes, glycyrrhetinic acid helps address dullness and sensitivity, and a synthetic peptide blend called Matrixyl 3000 improves firmness. “I love that it also uses a blend of optical diffusers to help disperse the light,” reducing the look of dark circles instantly, Dr. Garshick adds. For those with sensitive skin, this formula is fragrance-free, paraben-free and dye-free.

Pros: Targets signs of aging, reduces the look of dark circles instantly Cons: Expensive

Key ingredients: Caffeine, glycyrrhetinic acid, Matrixyl 3000 (peptides), glycerin

Also targets: Fine lines and wrinkles, sagging

The INKEY List Caffeine Eye Cream

Best affordable caffeine eye cream: The INKEY List Caffeine De-Puffing + Dark Circle Eye Cream


As a more affordable alternative with similar ingredients, Dr. Garshick likes The INKEY List caffeine eye cream which also contains the winning combo of caffeine and Matrixyl 3000 to help depuff and reduce the appearance of wrinkles over time. This $11 formula is also notably hydrating, thanks to the addition of glycerin (a humectant) and squalane (an emollient) which helps seal in moisture.

Pros: Affordable Cons: Contains alcohol, which can be irritating for sensitive skin

Key ingredients: Caffeine, Matrixyl 3000 (peptides), glycerin, squalane

Also targets: Fine lines and wrinkles, dryness

Cerave Skin Renewing Eye Cream

Best for sensitive skin: CeraVe Skin Renewing Eye Cream

“Containing peptides in addition to caffeine, ceramides, hyaluronic acid, and niacinamide, this drugstore eye cream is a multitasker,” says Dr. Garshick. For a budget-friendly product, it has a stacked ingredient list: ceramides help strengthen delicate under-eye skin, hyaluronic acid draws in moisture, niacinamide calms irritation (and helps with moisture retention), peptides help stimulate collagen production to target signs of aging, and caffeine depuffs. It’s also notably gentle. “CereVe is my go to brand during rosacea flare-ups,” says Glamour contributor Macaela MacKenzie . “This eye cream is a staple for me since it never causes irritation and always feels so soothing. I’m a fan of using this one in the evenings before slathering on a layer of CereVe’s thickest moisturizing cream in the winter.” It’s lightweight, absorbs easily and is gentle enough to be used twice daily, adds Dr. Garshick.

Pros: Gentle, budget-friendly Cons: The tube is prone to falling over in your medicine cabinet.

Key ingredients: Caffeine, ceramides, hyaluronic acid, niacinamide, peptides

Also targets: Dryness, irritation, signs of aging

Charlotte Tilbury Cryo Recovery Eye Serum

Most luxurious: Charlotte Tilbury Cryo Recovery Eye Serum

If you want to add a little luxury to your morning skincare routine, Dr. Garshick likes Charlotte Tilbury’s Cryo Recovery Eye Serum (another personal favorite of hers). “It uses a metal applicator to provide an instant cooling effect to immediately depuff,” she says. In addition to caffeine, this under eye cream contains peptides “leaving the under eye area looking smoother, brighter and refreshed." Apply in the a.m. for the most impactful results.

Pros: Creates a blurring effect that helps reduce the appearance of dark circles instantly Cons: Pricey, contains alcohol which can be irritating for sensitive skin

Key ingredients: Caffeine, peptides, glycerin

Also targets: Dark circles

By Emily Tannenbaum

By Elizabeth Logan

By Hanna Lustig

Sunday Riley Auto Correct Eye Cream

Best for dark circles: Sunday Riley Auto Correct Eye Cream

“Since my son was born last year, I’ve been dealing with persistent dark circles and under-eye bags,” says MacKenzie. “I started using this a few months ago and noticed an immediate difference in under-eye puffiness. I use it in the mornings to get the most benefit—it doesn’t pill under makeup, which is a must—but it’s also so gentle that I often use it at night as well.” Dr. Garshick calls out the addition of Brazilian ginseng root extract, which works with the formula's caffeine to reduce puffiness “and instantly give a more rested and brighter appearance while also boosting hydration,” she says.

Pros: Immediately depuffs Cons: Pricey

Key ingredients: Caffeine, Brazilian ginseng root, cocoa and shea butters

Also targets: Signs of aging, dryness

14 Hair-Growth Products That Experts Say Actually Work

Best for eye puffiness: Dermalogica Awaken Peptide Eye Gel

Like many of the best caffeine eye creams, Dermatologica’s Awaken Peptide Depuffing Eye Gel contains peptides to increase firmness in the delicate skin around the eyes, thereby reducing puffiness. It’s the addition of rosemary leaf extract that makes it one of Dr. Ahram’s favorites thanks to the ingredients known calming effects that make it ultra soothing. This helps balance out the formula’s lactic acid, an exfoliator that can help reduce the appearance of pores and fine lines.

Pros: Provides gentle exfoliation suitable for sensitive skin Cons: Expensive, rolls around in your medicine cabinet

Key ingredients: Caffeine, peptides, rosemary leaf extract, lactic acid, glycerin

Also targets: Dryness, sensitivity

Origins GinZing Refreshing Eye Cream

Best with vitamin c: Origins GinZing Refreshing Eye Cream

Dr. Arora is a fan of this brightening eye cream from Origins. Coffee bean extract and ginseng both help to address puffiness while vitamin C and niacinamide work at the cellular level to brighten under-eye skin and fight free-radicals. “I find myself gravitating towards this eye cream (and Origins’ matching GinZing moisturizer) in the summer. Something about the smell—floral and fruity—makes me feel like I’m on vacation,” says MacKenzie. “More importantly, it glides on really smoothly, doesn’t irritate my sensitive skin, and has a pearly pink tint that works a little bit like a concealer and helps camouflage dark under-eye circles.”

Pros: Smells nice Cons: Contains pigment, so you may not want to use it at night

Key ingredients: Caffeine, panax ginseng, vitamin C, niacinamide

Also targets: Dark circles, dryness

TruSkin Depuffing Longevity Eye Cream

Best retinol alternative: TruSkin Longevity Depuffing Eye Cream

If you’re sensitive to retinol, Dr. Garshick recommends TruSkin’s Depuffing Longevity Eye Cream. It contains bakuchiol, a plant-based retinol alternative that tends to be better tolerated—especially when it comes to the sensitive skin around the eyes. The caffeine in this formula comes from coffeeberry extract; lingonberry stem cells “help reduce puffiness and brighten the skin,” says Dr. Garshick. “I also love that the lingonberry stem cells protect against blue light damage and oxidative stress.”

Pros: Gentle retinol alternative suitable for all skin types Cons: You may not notice instant results

Key ingredients: Coffeeberry extract, lingonberry stem cells, bakuchiol

Also targets: Signs of aging, cellular damage

DRMTLGY Brightening Eye Masks

Best eye mask: DRMTLGY Brightening Eye Masks

While not technically an eye cream, Dr. Garshick loves DRMTLGY’s iconic Brightening Eye Masks for delivering the benefits of caffeine in a more intensive way. Caffeine depuffs, hyaluronic acid moisturizes, and niacinamide has a brightening effect. “I love using these eye masks before an event. They did wonders for helping my tired eyes and diminishing under-eye bags when I was newly postpartum and had to appear on camera for work,” says MacKenzie. “If you really want to soothe, store them in the fridge. In addition to a pre-event ritual, I’ll also use these when I want that cucumber on the eyes spa feeling at the end of a long day.”

Pros: Soothing, instant reduction in puffiness Cons: Not for daily use

Key ingredients: Caffeine, hyaluronic acid, niacinamide

Colorescience Total Eye Firm and Repair Concentrate

Best for undereye bags: Colorescience Total Eye Firm and Repair Concentrate

Another favorite of Dr. Garshick’s, Colorescience Total Eye Firm and Repair Concentrate is particularly good for those with dry skin, she says. It humectants glycerin and sea buckthorn fruit oil to draw moisture into the skin, and two emollients, meadowfoam seed oil and squalane, to seal it in. That support for the skin barrier can have a tangible impact on undereye bags as it helps to “improve the overall texture of the under eye skin,” she explains. Red microalgae works to boost collagen production and reduce the appearance of fine lines while peptides and caffeine depuff and help improve dark circles. “It’s safe for those with sensitive skin as it is free of parabens, phthalates and synthetic fragrance,” Dr. Garshick adds.

Pros: Ultra-hydrating, gentle enough for sensitive skin Cons: Expensive

Key ingredients: Caffeine, peptides, glycerin, sea buckthorn fruit oil, meadowfoam seed oil, squalane, red microalgae

Also targets: Signs of aging, skin texture

Neutrogena HydroBoost Caffeine Eye Gel Cream

Best drugstore pick: Neutrogena Hydroboost+ Caffeine Eye Gel Cream

This fragrance-free formula is first and foremost a dynamite moisturizer thanks to the inclusion of hyaluronic acid and glycerin. But dermatologists also love the actives. A blend of caffeine and peptides helps to depuff while also addressing dark circles overtime. “This eye cream is notably no frills—which isn’t a bad thing. While it may not tackle additional skin issues, it does do a solid job of moisturizing and depuffing without causing irritation or breaking the budget,” says MacKenzie. Plus it’s fragrance-free. “Especially for sensitive skin, it’s important to find formulas that are gentle and free from irritants like fragrance and alcohol,” says Dr. Arora.

Pros: Hydrating Cons: You may not see dramatic results

Key ingredients: Caffeine, peptides, hyaluronic acid

Neocutis Lumiere Firm Illuminating Tightening Eye Cream

Best brightening caffeine eye cream: Neocutis Lumiere Firm Illuminating Tightening Eye Cream

“This brightening eye cream combines glycyrrhetinic acid to help lighten the under eyes and sodium hyaluronate to help hydrate the skin,” says Dr. Garshick. Caffeine reduces under-eye puffiness and vitamin C has a brightening effect. What really makes this eye cream stand out, however, is the addition of growth factors—proteins found in the skin which are thought to have anti-aging benefits thanks to their ability to encourage the natural production of collagen and hyaluronic acid. Notably, “it is gentle enough to be used twice per day and won’t clog the pores,” adds Dr. Garshick.

Pros: Contains growth factors to boost collagen production Cons: Expensive

Key ingredients: Caffeine, growth factors, glycyrrhetinic acid, sodium hyaluronate, caffeine, vitamin C

Also targets: Anti-aging

Clinique PepStart Eye Cream

Best for fine lines: Clinique Pep-Start Eye Cream

“My grandmother is the person who first introduced me to Clinique as a young teen and it’s remained a part of my beauty routine in some way, shape or form, ever since,” says MacKenzie. “Pep-Start is a favorite for many reasons: it absorbs quickly, making it a good choice for morning application, it contains peptides to address the fine lines I’m starting to get, and the fun applicator tip makes every application into a mini massage.”

Pros: Portable, super easy to throw into a travel bag Cons: Can be hard to control how much you apply

Key ingredients: Caffeine, peptides

Also targets: Fine lines

The primary function of a good eye cream is to hydrate the particularly delicate skin around the eyes. But ideally you...

What to look for in an eye cream

The primary function of a good eye cream is to hydrate the particularly delicate skin around the eyes. But ideally, you want your eye cream to do more. Here’s what to look for to get the most bang for your buck:

Moisturizing ingredients: For optimal hydration, look for eye creams that contain humectants—substances that attract water, thereby drawing moisture into the skin—like hyaluronic acid, glycerin and alpha hydroxy acids.

Active ingredients: “To make an eye cream different from a regular facial moisturizer, it should include something in addition to a moisturizer like caffeine, retinol, niacinamide, or peptides,” says Dr. Ahram. Caffeine can depuff under-eye bags, retinol boosts collagen production to improve the appearance of fine lines and wrinkles, niacinamide helps brighten dark circles, and peptides boost firmness and elasticity.

SPF: The area around the eyes is likely the most overlooked spot in your sunscreen routine. Eye creams with added SPF ensure you’re protecting this sensitive skin from UV damage.

Texture: For ease of application, consider an eye cream’s texture. You don’t want anything too heavy or thick. Gels, creams, and serum formulations can all glide on easily, says Dr. Arora.

Packaging: Packaging matters—but not just for aesthetics. “Look for packaging that minimizes exposure to air and light to keep active ingredients stable,” says Dr. Arora. Airless pumps are ideal for keeping your eye cream fresh.

Caffeine is a triple threat when it comes to targeting issues common around the eyes. First and foremost caffeine...

The benefits of caffeine eye cream

Caffeine is a triple threat when it comes to targeting issues common around the eyes. First and foremost, caffeine constricts blood vessels in the skin, which can reduce swelling and puffiness almost instantly. That also leads to benefits overtime. “By improving circulation, caffeine can help diminish the appearance of dark circles under the eyes,” says Dr. Arora. Finally, caffeine is an antioxidant, which means it “helps protect the skin from environmental stressors,” he says.

Technically the best caffeine eye creams can be used morning or night  but all three dermatologists we spoke with said...

When's the best time to use eye cream

Technically, the best caffeine eye creams can be used morning or night (or both) but all three dermatologists we spoke with said you’ll see the biggest depuffing benefits if you incorporate one into your morning skincare routine. “Some people will even put their caffeine eye serums in the fridge to help provide a cooling effect which can also help with puffiness and decrease fluid retention around the eyes,” Dr. Arahm says. Apply eye cream after cleansing and serums but before moisturizer and SPF.

Caffeine eye creams tend to work well with a retinol routine. “Retinol can help boost the collagen in the eyelid skin...

Can caffeine eye creams be used with retinol?

Caffeine eye creams tend to work well with a retinol routine. “Retinol can help boost the collagen in the eyelid skin, which is the thinnest skin in the body,” says Dr. Arahm. “However, because the skin is thin, it may be more sensitive to irritation, so you may only be able to tolerate retinol 2-3 nights per week, while caffeine should be more tolerable and less irritating [for daily use].”

These Are the Best At-Home Red Light Therapy Devices

By Paula Lee

We Found the Most Comfortable Ballet Flats

By Brittany Romano

14 Hair-Growth Products That Experts Say Actually Work

By Neha Tandon


Here’s how much caffeine is in Panera’s Charged Lemonade, Starbucks coffee, Celsius and other popular drinks

How much caffeine is in your daily coffee or energy drink — and is it dangerous? 

A third lawsuit against Panera Bread over the chain’s caffeinated Charged Lemonade may have given some folks renewed jitters about whether their go-to energy drink is safe to sip. 

The latest legal complaint alleges that a 28-year-old Rhode Island athlete had to be hospitalized in April 2023 after developing heart palpitations and dizziness the day after drinking two and a half servings of Charged Lemonade, which can contain up to 390 milligrams of caffeine in a 30-ounce serving . The plaintiff, Lauren Skerritt, says the drink was advertised as “plant-based” and “clean.” But the day after consuming it, according to the suit, she was diagnosed with atrial fibrillation — aka an irregular heartbeat, which can lead to a stroke, heart complications and other serious health problems. The suit, filed last week, also alleges that Skerritt continues to suffer ongoing symptoms almost a year later, CBS News reported .

This comes a few months after two other suits implicated Panera’s caffeinated drink in the deaths of two customers. Florida resident Dennis Brown, 46, suffered a fatal cardiac arrest on Oct. 9 after drinking three Charged Lemonades. It should be noted that the complaint, as reported by NBC News , shared that Brown had underlying health issues. 

The family of college student Sarah Katz, 21, has also implicated Panera’s Charged Lemonade in her September 2022 death, according to a lawsuit filed in the Philadelphia Court of Common Pleas. Katz, who had a heart condition, died later the same day that she drank the caffeinated lemonade. The suit brought by her parents accuses the chain of failing to warn consumers about the drink’s ingredients. 

The company was not immediately available for comment. It has started displaying an enhanced caffeine disclosure about its Charged Lemonade, however. Its menu website now notes that these drinks contain caffeine, warning that the lemonades should be consumed in moderation and are not recommended for “children, people sensitive to caffeine, [and] pregnant or nursing women.”

How much caffeine is in your favorite energy drink?

So, is 390 milligrams a lot of caffeine for one drink? 

It’s quite a lot, in fact. Healthy adults should stick to less than 400 milligrams of caffeine a day, according to the Food and Drug Administration . The problem is that many people are probably consuming more of the stimulant than they realize, maybe even well exceeding the recommended daily limit, which could pose health risks like insomnia, nervousness, restlessness, nausea, increased heart rate and other side effects . 

But what does 400 milligrams of caffeine actually look like? 

That’s about eight cans of Diet Coke (or 11 cans of regular Coke ), or four cups of home-brewed coffee, so you probably don’t have to worry about completely giving up your favorite coffee or caffeinated drink just yet. ( Unless it’s loaded with sugar , which is another story.) The FDA notes that a 12-ounce can of a caffeinated soft drink typically contains 30 to 40 milligrams of caffeine, an 8-ounce cup of green or black tea counts 30 to 50 milligrams and an 8-ounce cup of coffee is closer to 80 to 100 milligrams. 

It’s important to know the portion size. Keep in mind that a standard cup is 8 ounces — less than what you might consider a cup of coffee to be. A single grande hot drip coffee at Starbucks for example, is 16 ounces — that’s two 8-ounce cups of coffee. Many standard mugs or coffeehouse servings today are 12 to 16 ounces. 

The caffeine content of different coffee brews and other drinks can vary widely. As detailed on Starbucks’s site , a grande, or 16-ounce, Pike Place Roast coffee contains 310 milligrams of caffeine — meaning that with that single drink, you are already almost hitting your daily recommended caffeine limit. That’s before you consider any other source of caffeine you might be consuming throughout the day, like a second cup of coffee, tea, soda, energy drinks, chocolate or certain supplements. Some painkillers, like those targeting headaches, might also have caffeine in them.

The American Academy of Pediatrics advises against kids under 12 consuming any caffeine at all, and recommends that teens age 12 to 18 consume less than 100 milligrams of caffeine a day.

The recommended daily caffeine limit is even lower for kids and teens. In fact, the American Academy of Pediatrics advises against kids under 12 consuming any caffeine at all, writing, “There is no proven safe dose of caffeine for children.” The AAP recommends that teens age 12 to 18 consume less than 100 milligrams of caffeine — about the amount in two 12-ounce cans of soda — a day. But energy drinks like Celsius and Prime that are popular on TikTok may pack an overcaffeinated punch that easily exceeds that 100-milligram limit. A single 12-ounce can of Celsius Original contains 200 milligrams of caffeine, for example, while Celsius Heat has 300 milligrams of caffeine in a single 16-ounce can. That’s double and triple the recommended daily limit for teens. 

On the flip side, Red Bull has a relatively low 80 milligrams of caffeine in a single 8.4-ounce can — well below the amount in that Starbucks coffee. 

Caffeine counts can get confusing, so here’s a chart comparing the caffeine content of some popular coffees, sodas and energy drinks to give you a better idea of how close a single serving comes to pushing you over the recommended 400-milligram limit for adults. 

Health experts told MarketWatch that many people aren’t worried about their caffeine intake the same way they may be about their sugar or sodium consumption. Kids, teens and young adults in particular don’t pay attention to these amounts, they say.

“I see a lot of younger patients, particularly young men, who are drinking these caffeinated drinks in the morning, or before they go to the gym, and the feeling is that it helps them perform better,” Dr. John Whyte, the chief medical officer at WebMD, told MarketWatch.

A recent Mintel market report valued the U.S. energy-drink industry at $21.1 billion worth of sales in 2022, and forecast it would hit $22.7 billion in 2023, largely thanks to young men. “Energy drinks are largely a younger consumers’ category, with men aged 18-34 leading consumption,” the report noted. But there’s plenty of potential to get more younger women on board, as “the narrowest gap exists between men and women for hybrid energy drinks (coffee, ice tea, etc.),” it added.

“The biggest myth is that ‘Caffeine doesn’t hurt me,’ because you don’t hear about it being regulated as much,” Whyte said, “and so people are more concerned about sugar and calorie counts than caffeine.”

Yet the FDA warns that toxic effects, like seizures, can be observed with the rapid consumption of around 1,200 milligrams of caffeine. 

“Caffeine itself, remember, is a stimulant,” Whyte said. “It’s going to increase your heart rate. It’s going to increase your blood pressure because it’s going to constrict the blood vessels and make your heart work harder and make it go faster. And it may make you more dehydrated.”

This can have a bigger effect on kids and teens, who are drawn to energy drinks in particular, noted Dr. Mark Corkins, the chair of the AAP committee on nutrition. “Kids think [caffeinated energy drinks] are cool,” Corkins told MarketWatch. “It’s an ‘adult’ drink. And we all like our stimulants. They make us feel good.”

But higher concentrations of caffeine can hit younger consumers harder than adults. “For a kid, one cup of coffee [or one energy drink] is a bigger dose per kilogram [of body weight] compared to a grown man,” he said.

So what should consumers know? 

First, be aware of the signs of caffeine overdose, which include: 

  • Anxiousness
  • Fast heart rate
  • Upset stomach
  • A feeling of unhappiness (dysphoria)

It’s important to read labels or look up a product’s nutrition information online to be aware of how much caffeine you are consuming.

“I don’t think anyone has a sense of what the generally recommended amount of caffeine is,” Whyte said. “So even if you see that a drink has 390 milligrams of caffeine in it, you don’t have a reference point” for whether that’s too much caffeine or not.

The bottom line: Adults should stick to less than 400 milligrams of caffeine a day. Teens age 12 to 18 should stay under 100 milligrams. And kids under 12 probably shouldn’t have any caffeine at all.

Here’s how much caffeine is in Panera’s Charged Lemonade, Starbucks coffee, Celsius and other popular drinks

For expository writing, our writers investigate a given idea, evaluate its various evidence, set forth interesting arguments by expounding on the idea, and that too concisely and clearly. Our online essay writing service has the eligibility to write marvelous expository essays for you.

buffalo case study caffeine

5 Signs of a quality essay writer service

buffalo case study caffeine

Customer Reviews


  1. Case study: Caffeine addiction

    buffalo case study caffeine

  2. Case study: Caffeine addiction

    buffalo case study caffeine

  3. buffalo case studies

    buffalo case study caffeine

  4. Case study: Caffeine addiction

    buffalo case study caffeine

  5. Caffeine Case Study

    buffalo case study caffeine

  6. Post-Study Caffeine Intake Enhances Memory Consolidation a New Study

    buffalo case study caffeine


  1. Buffalo Hypocalcemia case

  2. Gymrat’s HACK to clear exams💪🤓 #gym #preworkout #workout

  3. Study: Caffeine Poses Risk For Pregnancy


  1. NCCSTS Case Studies

    Enrich your students' educational experience with case-based teaching. The NCCSTS Case Collection, created and curated by the National Center for Case Study Teaching in Science, on behalf of the University at Buffalo, contains nearly a thousand peer-reviewed case studies on a variety of topics in all areas of science.

  2. PDF Case Workers Report Greater Caffeine Intake

    known literature exists describing caffeine intake among case workers. ... This cross-sectional study was approved by Buffalo State College, State University of New York Institutional Review Board. Case workers in the United States were recruited with the intent of snowball sampling. A brief study description with a link to the

  3. Addictive Effects of Caffeine on Kids Being Studied by UB

    BUFFALO, N.Y. -- Caffeine is a stimulant drug, although legal, and adults use it widely to perk themselves up: Being "addicted" to caffeine is considered perfectly normal. ... placebo-controlled, dose-response study of the effects of caffeine on the teenagers' blood pressure, heart rate and hand tremor. Two papers currently are being written ...

  4. The clinical toxicology of caffeine: A review and case study

    1. Introduction with a brief history of caffeine consumption Caffeine (1,3,7-trimethylxanthine) is a psychostimulant purine-like alkaloid, which is found naturally in coffee, tea, cacao beans (source for chocolate and cocoa) guarana, mate, and kola nuts, though it has been identified in more than 60 plant species [ 1, 2 ].

  5. Caffeine Use Disorder: A Comprehensive Review and Research Agenda

    Introduction. C affeine is the most widely used drug in the world. 1 In the United States, more than 90% of adults use it regularly, and, among them, average consumption is more than 200 mg of caffeine per day 2 —more caffeine than is contained in two 6-ounce cups of coffee or five 12-ounce cans of soft drinks. 3,4 Although consumption of low to moderate doses of caffeine is generally safe ...

  6. Case Report: Dangerous mistake: an accidental caffeine overdose

    Caffeine (1,3,7-trimethylxanthine) is a natural product commonly presented in food's composition, beverages and medicinal products. Generally, it is thought to be safe under normal dosage, yet it can be fatal in case of severe intoxication. We report a case of a healthy 32-year-old woman who went to the local emergency department (ED) 30 min ...

  7. Study finds no association between caffeine ...

    BUFFALO, N.Y. — Researchers from the University at Buffalo conducted a study of nearly 80,000 postmenopausal women in the U.S. to determine whether caffeine consumption from coffee and tea has any association with invasive breast cancer. ... "The overlap of age at diagnosis of breast cancer and age with high consumption of caffeine, and the ...

  8. Study finds no association between caffeine ...

    Overlap of age at diagnosis of breast cancer and age with high consumption of caffeine, and inconsistent findings from previous studies, motivated researchers to study whether caffeine could affect breast cancer risk.

  9. PDF Why homeostasis is important to everyday activities

    2. Compare/contrast respiratory acidosis to the case study scenario. 3. Suppose you were to drink an energy drink (with caffeine or another stimulant like guarana or gensing) while consuming alcohol. Would there be an impact on the amount of alcohol consumed? Please explain in terms of the acid-base balance in your body.

  10. Caffeine's Dirty Little Secret

    Caffeine routinely leads to jitteriness, nervousness, sweating, insomnia, and rapid heartbeat. If mild, such symptoms can be well worth the benefits. But consuming too much caffeine can have ...

  11. Caffeine

    In the U.S., adults consume an average of 135 mg of caffeine daily, or the amount in 1.5 cups of coffee (1 cup = 8 ounces). [5] The U.S. Food and Drug Administration considers 400 milligrams (about 4 cups brewed coffee) a safe amount of caffeine for healthy adults to consume daily. However, pregnant women should limit their caffeine intake to ...

  12. Health Effects of Caffeine

    And Cooper notes that if you consume 10 grams (or 10,000 milligrams) of caffeine - equivalent to what would be found in about 100 cups of coffee - that amount of caffeine can be fatal.

  13. Caffeine: How much is too much?

    Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks. Caffeine in powder or liquid form can ...

  14. How much caffeine is too much? Here's what to know before having ...

    Too much caffeine can cause headaches, insomnia, anxiety, muscle tremors and long-term impacts. ... A 2021 study found pregnant people who consumed less than 200 milligrams of caffeine per day ...

  15. Did you know there's caffeine in other items that are not ...

    While most adults can safely consume 400 mg of caffeine - or about four cups of brewed coffee - a day without any side effects, it's not just about keeping track of your coffee consumption ...

  16. Caffeine Intake and Mental Health in College Students

    College students use very high doses of caffeine, an average of over 800 mg/day, which is approximately double the recommended safe dosage [ 3 ]. The short-term and long-term effects of caffeine on the human body have been studied. Research to date has primarily focused on caffeine's exacerbation of anxiety, sleep disorders, and depression in ...

  17. 7 Benefits of Quitting Caffeine That Make It Worth the Struggle

    According to a 2023 study published in European Review for Medical and Pharmacological Sciences, between 80% and 90% of US adults and children have caffeine on a regular basis. 1

  18. The clinical toxicology of caffeine: A review and case study

    1. Introduction with a brief history of caffeine consumption. Caffeine (1,3,7-trimethylxanthine) is a psychostimulant purine-like alkaloid, which is found naturally in coffee, tea, cacao beans (source for chocolate and cocoa) guarana, mate, and kola nuts, though it has been identified in more than 60 plant species [1, 2].It has been consumed for thousands of years by humans with stories ...

  19. Another person has died and family blames Panera's 'charged ...

    How much caffeine is dangerous? One cup of coffee has about 95 milligrams of caffeine and one 12-ounce Red Bull has 111. Registered dietician Jordan Hill previously told USA TODAY the recommended ...

  20. How Much Caffeine You Should Actually Have—and When

    (No, that 20-ounce Starbucks Venti doesn't count as one cup of coffee.) And believe it or not, we are doing pretty well on this target. The average American adult consumes about 200 milligrams ...

  21. Grapefruit could prolong the effects of caffeine: scientist

    Eating grapefruit with your java could potentially extend the effects of the caffeine and ward off that unwanted afternoon slump, according to Michelle Francl, a chemistry professor at Bryn Mawr ...

  22. Buffalo Case Study Caffeine

    Buffalo Case Study Caffeine | Best Writing Service. Alexander Freeman. #8 in Global Rating. 1 (888)814-4206 1 (888)499-5521. Hire a Writer.

  23. Buffalo Case Study Caffeine

    Buffalo Case Study Caffeine - 8521 . Finished Papers. I'm new to this... 341 . Customer Reviews. PLAGIARISM REPORT. 94. Assignment, Linguistics, 2 pages by Rising Siri Kaewpakit. EssayService uses cookies to deliver the best experience possible. Read more. Buffalo Case Study Caffeine: 4.7/5. 100% Success rate ...

  24. Buffalo Case Study Caffeine

    Buffalo Case Study Caffeine | Best Writing Service 7Customer reviews 260 King Street, San Francisco Updated Courtyard facing Unit at the Beacon! This newly remodeled… Bedrooms 2 Get access to the final draft You will be notified once the essay is done.

  25. Coffee and Caffeine Consumption for Human Health

    According to the review by Jee et al., coffee/caffeine neuroprotective effects seem to be broader and sex- and age-specific. Indeed, they concluded that caffeine consumption reduces the risk of stroke, dementia, and depression in women and that of PD in men. Nevertheless, it may increase sleep disorders and anxiety disorders in adolescence in ...

  26. 13 Best Caffeine Eye Creams 2024, Tested by Dermatologists

    Best caffeine eye cream for sensitive skin: CeraVe Skin Renewing Eye Cream Best for dry skin: Colorescience Total Eye Firm and Repair Concentrate , $94 Best caffeine eye mask: DRMTLGY Brightening ...

  27. Here's how much caffeine is in Panera's Charged Lemonade ...

    The American Academy of Pediatrics advises against kids under 12 consuming any caffeine at all, and recommends that teens age 12 to 18 consume less than 100 milligrams of caffeine a day.

  28. Buffalo Case Study Caffeine

    Buffalo Case Study Caffeine | Top Writers ID 6314 Thesis on Management 4.8/5 Andre Cardoso #30 in Global Rating Buffalo Case Study Caffeine 296 Customer Reviews Dr.Jeffrey (PhD) #4 in Global Rating Emery Evans #28 in Global Rating Follow Us Academic writing Check your email inbox for instructions from us on how to reset your password. 535

  29. Dongyu Caffeine Eye Serum: $16, 'Reduces Puffiness Almost ...

    Give your skin a boost with the Dongyu 5% Caffeine Eye Serum and Under Eye Roller. When used twice a day, this eye serum effectively transforms dark under eye circles and puffiness into lighter ...