Harvard Health Experts and Contributors

Peter Grinspoon, MD

Contributor; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Peter Grinspoon is a primary care physician, educator, and cannabis specialist at Massachusetts General Hospital; an instructor at Harvard Medical School; and a certified health and wellness coach. He is the author of Seeing Through the Smoke: A Cannabis Specialist Untangles the Truth About Marijuana, as well as the groundbreaking memoir Free Refills: A Doctor Confronts His Addiction. He is a board member of the advocacy group Doctors for Cannabis Regulation. He is also a TedX speaker and commonly lectures on the topics of cannabis, psychedelics, addiction, opioids, and physician health.

Staci Gruber, PhD

Contributor

Dr. Staci Gruber received her PhD from Tufts University, and is currently an associate professor of psychiatry at Harvard Medical School and the director of the Cognitive and Clinical Neuroimaging Core at McLean Hospital. Over the last several decades, her research has focused on the application of neurocognitive models and brain imaging to characterize risk factors for substance abuse and psychiatric conditions. Specifically, she has extensively researched the impact of recreational cannabis use on the brain using neurocognitive measures, clinical assessments, and brain imaging techniques. Given inherent differences between recreational and medical cannabis use, Dr. Gruber founded the Marijuana Investigations for Neuroscientific Discovery (MIND) program, designed to clarify the specific effects of medical cannabis use through observational, longitudinal, and survey studies, as well as innovative clinical trials. Recently, Dr. Gruber launched the Women’s Health Initiative at MIND (WHIM), the first cannabis-focused program designed specifically to address women’s health and disorders that disproportionately affect women as well as some transgender and nonbinary individuals.

Perihan Esra Guvenek-Cokol

Contributor

Perihan Esra Guvenek-Cokol, MD, is double board-certified as a child/adolescent and adult psychiatrist. She specializes in emerging mental illness in teens and young adults. Her expertise is in the early stages of psychotic and bipolar disorders, along with anxiety and obsessive-compulsive disorders. Dr. Guvenek-Cokol serves as the medical director for McLean Hospital's Child and Adolescent OCD Institute (OCDI Jr.) and the Support, Treatment, and Resilience (STAR) program, an outpatient program for teens and young adults. She is an instructor in psychiatry at Harvard Medical School.

Samar Hafida, MD

Contributor

Samar Hafida, MD, is an adult endocrinologist at Joslin Diabetes Center in Boston, MA. Her special interests include weight management and the effect of metabolic surgery in the management of type 2 diabetes. In addition to her clinical work, Dr. Hafida is passionate about medical education and delivery of diabetes care to health systems. She is assistant director of global education and is involved in several education initiatives geared to a wide variety of learners and provides consultation to health systems on reforming diabetes care and improving outcomes.

Kathleen Haley, MD

Contributor

Kathleen J. Haley, MD, is a physician in the Pulmonary and Critical Care Division at the Brigham and Women’s Hospital. She graduated from the Pennsylvania State University College of Medicine and then completed an Internal Medicine Residency at the New England Deaconess Hospital followed by fellowships in Pulmonary Medicine at the New England Deaconess Hospital and Critical Care Medicine at the Brigham and Women’s Hospital. Dr. Haley is an Assistant Professor of Medicine at Harvard Medical School and an Associate Physician at the Brigham and Women’s Hospital, where she attends in the Medical and Thoracic Intensive Care Units. Additionally, she serves as the Medical Director for the BWH Ventilator Service at Spaulding Hospital Cambridge. She is active in clinical research, where her interests include asthma and chronic critical illness.

Daniel L. Hall, PhD

Contributor

Daniel L. Hall, PhD, is a licensed clinical health psychologist, Harvard Medical School integrative medicine research fellow, and a clinical fellow in psychology in the department of psychiatry at Massachusetts General Hospital (MGH). He works with clinical research teams at the MGH Behavioral Medicine program, the Benson-Henry Institute for Mind Body Medicine, the MGH Cancer Center, and the division of general medicine at Beth Israel Deaconess Medical Center. Dr. Hall’s research examines how medical patients experience and cope with uncertainty and stress arising from cancer and other chronic illnesses. He is currently testing a multimodal mind-body intervention to help ease fear of cancer recurrence.

Florencia Halperin, MD

Contributor

Florencia Halperin, MD, is the co-founder and Co-Director of the Center for Weight Management and Metabolic Surgery at Brigham and Women’s Hospital, and Chief of Endocrinology at Brigham and Women’s Faulkner Hospital. Her clinical research is focused on the delivery of weight loss interventions, as well as on the metabolic effects of bariatric surgery. Her clinical research is complemented by her clinical practice focused on the management of obesity and diabetes.

Matthew Hamilton, MD

Contributor

Dr. Matthew Hamilton is an associate gastroenterologist at Brigham and Women’s Hospital, and an assistant professor of medicine at Harvard Medical School. He currently serves as the director of the inflammatory bowel disease fellowship and IBD education programs.

Syed Moin Hassan, MD

Contributor

Dr. Hassan is currently a sleep medicine fellow at Brigham and Women’s Hospital and Massachusetts General Hospital, and a research fellow at Harvard Medical School. He is also the recipient of the Academic Sleep Pulmonary Integrated Research/Clinical Fellowship (ASPIRE) from the American Thoracic Society. His research interests include sleep-disordered breathing and pulmonary hypertension.

Kathryn Hatch, MD

Contributor

Kathryn M. Hatch, MD is the Director of Refractive Surgery at Massachusetts Eye and Ear and the Site Director of Mass. Eye and Ear Waltham. She is an Assistant Professor of Ophthalmology at Harvard Medical School. She is an accomplished surgeon in all-laser refractive surgery techniques including, LASIK and PRK, complex and refractive laser-assisted cataract surgery with intraoperative aberrometry, corneal crosslinking and Intacs (intrastromal corneal ring segments) for keratoconus and post-LASIK ectasia as well as advanced techniques in corneal transplant surgery. Since joining the staff, she has assisted in bringing new technologies to Mass. Eye and Ear including refractive laser-assisted cataract surgery with intraoperative aberrometry, collagen crosslinking, inlays for presbyopia, the Visumax laser (the only laser which performs the small incision lenticule extraction procedure, or SMILE, for the refractive surgical treatment of myopia), and lipiflow for dry eye disease. Dr. Hatch is considered a key opinion leader in the treatment of keratoconus and has been performing collagen crosslinking since 2011. She was an investigator in phase IV clinical trial in which she was performing minimally invasive crosslinking for greater than 5 years. In 2016, she became the first person at Mass. Eye and Ear to perform crosslinking with the FDA-approved technology and is one of the busiest crosslinking specialists in the US. She is embarking in a research project to assist in developing a screening tool for keratoconus and post-LASIK ectasia. Additionally, Dr. Hatch has experience in the treatment of ocular surface disease and dry eye, corneal dystrophies and anterior segment reconstruction. She performs cutting-edge corneal transplantation surgery, including both full thickness penetrating keratoplasty and partial thickness transplant surgery, DSAEK (Descemet Stripping Automated Endothelial Keratoplasty), DMEK (Descemets Membrane Endothelial Keratoplasty), and DALK (Deep Anterior Lamellar Keratectomy). She also performs IEK (Intralase Enabled Keratoplasty) and IE-DALK (Intralase Enabled Deep Anterior Lamellar Keratoplasty) and was the first eye surgeon in New England to perform IE-DALK. Dr. Hatch is an active fellow of the American Academy of Ophthalmology and a diplomat of the American Board of Ophthalmology. She is a member of several organizations including the New England Ophthalmic Society, the Cornea Society, the American Society of Progressive Enterprising Surgeons, the American European College of Ophthalmic Surgeons and the Massachusetts Medical Society. She has been in invited speaker at several regional, national and international meetings. In 2016 and 2017, Dr. Hatch was selected as one of the 300 Premier Innovators in refractive cataract surgery in the United States by Ocular Surgery News.

Marissa Hauptman, MD, MPH

Contributor

Dr. Marissa Hauptman is a board-certified pediatrician and associate director of the Pediatric Environmental Health Center; associate director of the Boston Children's Hospital Pediatric and Reproductive Environmental Health Fellowship Program and the Region 1 New England pediatric environmental health specialty unit at Boston Children’s Hospital, where each week she provides multidisciplinary care for children with lead exposure; and an instructor in pediatrics at Harvard Medical School. Dr. Hauptman’s research focuses on using spatial analysis techniques to research and improve environmental and social health disparities in children with chronic diseases. She earned her MD from New York University School of Medicine, and also holds a masters in public health from Brown University.

Chester Hedgepeth, III, MD, PhD

Contributor

Chester M. Hedgepeth, III, MD, PhD, is a cardiovascular specialist at Brigham and Women’s Hospital (BWH) and an instructor in medicine at Harvard Medical School. Dr. Hedgepeth also serves as the executive chief of cardiology for the Care New England Health System, and chief of cardiology at Kent and Memorial Hospitals in Rhode Island. Dr. Hedgepeth received his medical degree from Perelman School of Medicine at the University of Pennsylvania. He completed an internal medicine residency and fellowships in cardiovascular disease and electrophysiology at BWH. He is board certified in both internal medicine and cardiovascular disease. Dr. Hedgepeth founded, and currently leads, the BWH/Kent Hospital cardiac telemedicine service, which provides consultative support for Kent Hospital. His clinical and research interests include coronary artery disease, cardiomyopathies, congestive heart failure, cardiac arrhythmia, and the mechanisms of arrhythmic death after myocardial infarction. His research has received support from the National Institutes of Health.

Jeffrey S. Heier, MD

Contributor

Dr. Jeffrey S. Heier is the director of the retina service and director of retina research at Ophthalmic Consultants of Boston. He is the past president of the Retina Society, a member of the American Society of Retina Specialists executive committee, the past president of the New England Ophthalmological Society, and a member of the Macula Society. He is one of the leading retinal clinical researchers in the country for new treatments in retinal disease. He is a scientific advisor to many biotechnical or pharmaceutical companies, lectures nationally and internationally, and has authored numerous peer-reviewed works. Dr. Heier received his medical degree from Boston University, completed an internship and residency at Fitzsimons Army Medical Center, and a vitreoretinal fellowship at OCB/Tufts School of Medicine. He served as a physician in a combat support hospital in the Persian Gulf War, where he was awarded a Bronze Star.

Joyce Hendley

Health Writer

Joyce Hendley is an award-winning writer and editor who is passionate about exploring the connections between food and health. A longtime nutrition journalist and a former food editor, her work has appeared in dozens of health-focused sites, publications, and cookbooks, including EatingWell, WW, Diabetic Living, The American Diabetes Association, and the Institute of Natural Medicine. Based in Cortez, Florida, Joyce is also an adjunct lecturer in public communication at the University of Vermont. She holds a master’s degree in nutrition and food science from New York University.

Brandi Henson, PsyD

Contributor

Brandi S. Henson, PsyD, is an Attending Psychologist in the Department of Psychiatry at Boston Children’s Hospital and a Clinical Instructor of Psychiatry at Harvard Medical School. Her clinical and research interests are in the neurodevelopmental trajectories of children and adolescents with congenital heart disease and associated genetic syndromes.

David Hepner, MD, MPH

Contributor

David Hepner, MD, MPH, is medical director of the Weiner Center for Preoperative Evaluation at the Brigham and Women’s Hospital, and associate professor of anesthesia at Harvard Medical School. He is an associate faculty member of Ariadne Labs. His clinical and research interests in preoperative assessment, and his vision of a society in the area of preoperative assessment and its impact on surgical outcomes, led him to be one of the cofounders in 2005 of the Society for Perioperative Assessment and Quality Improvement, an international multidisciplinary society. Since then, he has been an active participant in improving surgical outcomes by sharing best practices, promoting research, and enhancing communication among health professionals across multiple disciplines. Dr. Hepner is a founding member of the Emergency Manual Implementation Collaborative, whose goal is to foster the dissemination and effective use of emergency checklists to enhance patient safety. He has helped lead expert panel interactive discussions on progress toward effective use of emergency manuals in hospitals across the country and helped develop an implementation toolkit. Dr. Hepner received his BA from Clark University, his MPH from Harvard School of Public Health, and his MD from Medical College of Wisconsin. His clinical training includes internship in medicine at the Washington University School of Medicine, and residency in anesthesiology and fellowship in obstetric anesthesia at the Hospital of the University of Pennsylvania.

Kevin Hill, MD, MHS

Contributor

Dr. Kevin Hill is director of addiction psychiatry at Beth Israel Deaconess Medical Center, and an associate professor of psychiatry at Harvard Medical School. He earned a master’s in health science at the Robert Wood Johnson Clinical Scholars Program at the Yale School of Medicine. He most commonly treats patients who have problems with alcohol, cannabis, or opioids, and teaches medical students and physicians how to treat patients with addictions. The author of Marijuana: The Unbiased Truth about the World’s Most Popular Weed and coauthor of Medical Cannabis: An Evidence-Based Guide, Dr. Hill’s research interests include the development of medications to treat cannabis use disorder as well as cannabis policy, and he has published widely on these topics in such journals as JAMA, The American Journal of Psychiatry, JAMA Internal Medicine, and Lancet Psychiatry. He serves on the editorial boards of Cannabis and Cannabinoid Research and the American Journal on Addictions.

Eric Holbrook, MD

Contributor

Eric H. Holbrook, M.D. graduated from Cornell University with a Bachelors in Science and from the State University of New York Health Science Center in Syracuse with a Masters in Science and a Degree in Medicine. He completed a National Institutes of Health post-doctoral fellowship and residency in otolaryngology at the Medical College of Virginia/Virginia Commonwealth University. He completed further training with a fellowship in Rhinology and Sinus Surgery at the University of Nebraska Medical Center under Dr. Donald Leopold. He has been a member of the full time faculty at the Massachusetts Eye and Ear Infirmary (MEEI) since 2003, is an Associate Professor of Otolaryngology at the Harvard Medical School, and serves as the Chief of the Rhinology Division at MEEI. His principal clinical interests are diseases of the nose and sinuses, chronic rhinosinusitis, endoscopic skull base surgery, and olfactory disorders. His research interests include immunohistochemical characterization of human olfactory tissue, effects of odor exposure on olfactory regeneration, and manipulating human olfactory stem cells for potential restoration of function.

Sigmund Hough, PhD, ABPP/rp

Contributing Editor

Sigmund Hough, Ph.D., ABPP/rp received his A.B. from Columbia College, Columbia University, M.A. in Developmental Psychology from Columbia University, and Ph.D. in Clinical Psychology from Boston University. Dr. Hough holds ABPP board specialization in Rehabilitation Psychology. He is a Fellow in the National Academy of Neuropsychology, registered as a National Health Care Provider in Psychology, licensed in Massachusetts and Maine. He is a clinical rehabilitation neuropsychologist; Assistant Professor in the Department of Psychiatry, Harvard Medical School and Adjunct Assistant Professor of Psychiatry at Boston University School of Medicine. He has served in the capacity of Clinical Director and Director of Psychological services at private rehabilitation facilities, case reviewer for a nationwide managed care company, and as a clinical service provider in both the public, federal, state and private sector. He has served as Director, Postdoctoral Fellowship Training Program-Boston Consortium in Clinical Psychology. He has conducted nationwide Internship and Postdoctoral Training Site Reviews for the American Psychological Association. He conducts medical facility accreditation site surveys nationwide and internationally for the division of Medical Rehabilitation, CARF. He is an AASECT Certified Sex Therapist and Editor-in-Chief of the international journal Sexuality and Disability. Recipient of the 2004 Clinical Performance Award from The American Association of Spinal Cord Injury Psychologists and Social Workers and the 2005 Award for Excellence in Postdoctoral Training from The Association of Psychology Postdoctoral and Internship Centers (APPIC). As the Past Vice President of the Academy of Spinal Cord Injury Professionals, he currently serves on the Board of Directors.

Michael Hsu, MD

Guest Contributor

Dr. Michael Hsu is a resident psychiatrist and is currently the chief resident of outpatient psychiatry at Brigham and Women's Hospital, a teaching hospital of Harvard Medical School. After graduating from the University of Pennsylvania with degrees in business and computational biology, he worked at a global health care consulting firm before completing his medical degree at Johns Hopkins School of Medicine. He was awarded the 2021–2022 American Psychiatric Association/Substance Abuse and Mental Health Administration Substance Abuse Minority Fellowship, and the 2020 John Renner Travel Award by the American Academy of Addiction Psychiatry. He is passionate about healthcare equity and holistic/integrative approaches to mental health care, and has written and presented about internet gaming disorder, healthcare equity in addiction treatment, cannabis, and digital psychiatry. Following residency, he will pursue a one-year fellowship in addiction psychiatry at Emory University.

Frank Hu, MD, MPH, PhD

Contributor

Frank Hu, MD, MPH, PhD, is the Fredrick J. Stare Professor of Nutrition and Epidemiology and chair of the department of nutrition at the Harvard T.H. Chan School of Public Health. He is also professor of medicine at Harvard Medical School and Brigham and Women’s Hospital. His major research interests include epidemiology and prevention of cardiometabolic diseases through diet and lifestyle; gene-environment interactions and risk of obesity and type 2 diabetes; nutritional metabolomics in type 2 diabetes and cardiovascular disease; and nutrition transition, metabolic phenotypes, and cardiovascular disease in low- and middle-income countries. Dr. Hu serves as director of the Dietary Biomarker Development Center at Harvard University. He has published a textbook, Obesity Epidemiology (Oxford University Press), and more than 1,500 peer-reviewed papers. Dr. Hu served on the 2015 Dietary Guidelines Advisory Committee. He has served on the editorial/advisory board of The Lancet Diabetes & Endocrinology, Diabetes Care, and Clinical Chemistry. Dr. Hu was elected to the National Academy of Medicine in 2015.

Thomas Hübl

Guest Contributor

Thomas Hübl is a renowned teacher, and author of Healing Collective Trauma: A Process for Integrating Our Intergenerational and Cultural Wounds. Since 2002, he has led dialogue and restoration processes around collective trauma with more than 100,000 people worldwide. He has been teaching workshops on trauma-informed approaches, resilience, and mindfulness at Harvard since 2019.

Kimberly Humphrey, MD, MPH

Contributor

Dr. Kimberly Humphrey is an emergency physician, a current Fellow in Climate Change and Human Health at Harvard C-CHANGE at Harvard's T.H. Chan School of Public Health, and a visiting scholar at the Harvard FXB Center. Her research focuses on the intersection between climate change and health, particularly community and health system adaptation to climate change impacts, and she is passionately involved with advocacy, education, and policy development through NGOs and government-based roles focused on climate change and health.

Kristin Hung, MD

Contributor

Dr. Kristin Hung is board-certified in urogynecology and reconstructive pelvic surgery (URPS). She is an attending urogynecologist at Massachusetts General Hospital, and serves as division director of quality and clinical operations and instructor at Harvard Medical School. Dr. Hung treats patients with pelvic organ prolapse and urinary incontinence. She specializes in minimally invasive surgical approaches, including vaginal surgery, traditional laparoscopy, and robotic surgeries. Dr. Hung completed her fellowship in URPS at Massachusetts General Hospital and her residency in OB/GYN at Beth Israel Deaconess Medical Center, both in Boston. She obtained her medical degree from the University of Michigan and graduated magna cum laude from Harvard College with a bachelor's in history and science. Dr. Hung is a member of the American Urogynecologic Society and serves on its diversity, equity, and inclusion committee. Her research focuses on shared decision-making tools to improve patient care and outcomes, and health disparities in the treatment of pelvic floor conditions.

Nasrien Ibrahim, MD

Contributor

Nasrien Ibrahim, MD, is a board certified cardiologist in the Advanced Heart Failure and Transplant Section within the Division of Cardiology at the Massachusetts General Hospital (MGH) and an Instructor in Medicine at Harvard Medical School. She is also Associate Director of the Resynchronization & Cardiac Therapeutics Program at MGH. Dr. Ibrahim takes care of patients with advanced heart failure, left ventricular assist devices, and heart transplants. She completed her internal medicine residency and general cardiology fellowship at the University of Cincinnati Medical Center in Cincinnati, OH. Next, she completed a fellowship in advanced heart failure and cardiac transplant at the University of Colorado in Denver, CO. Following that, Dr. Ibrahim completed a fellowship in clinical research at MGH. She is involved in several research studies in heart failure involving biomarkers and participate in several clinical trials all aimed at improving the management and outcomes of patients with heart failure.

Harvard Health Experts and Contributors

List of Experts

Peter Grinspoon, MD

Staci Gruber, PhD

Perihan Esra Guvenek-Cokol

Samar Hafida, MD

Kathleen Haley, MD

Daniel L. Hall, PhD

Florencia Halperin, MD

Matthew Hamilton, MD

Syed Moin Hassan, MD

Kathryn Hatch, MD

Marissa Hauptman, MD, MPH

Chester Hedgepeth, III, MD, PhD

Jeffrey S. Heier, MD

Joyce Hendley

Brandi Henson, PsyD

David Hepner, MD, MPH

Kevin Hill, MD, MHS

Eric Holbrook, MD

Sigmund Hough, PhD, ABPP/rp

Michael Hsu, MD

Frank Hu, MD, MPH, PhD

Thomas Hübl

Kimberly Humphrey, MD, MPH

Kristin Hung, MD

Nasrien Ibrahim, MD