GLP-1 medications are changing the conversation around obesity, but are they really a magic bullet? In this masterclass, I bring together insights from leading experts to unpack how these medications work, who they’re for, and why long-term success still depends on nutrition, exercise, and addressing the food environment. Drawing on conversations with Dr Terry Simpson, Dr Federica Amati, Dr Mauricio Gonzalez, Dr Christos Mantzoros, and Dr Stephan Guyenet, we separate hype from evidence and explore what these drugs can, and can’t, do.
We explore why obesity is far more complex than a question of willpower, the science behind “food noise”, and why some people respond so differently to the same diet. We also dive into practical strategies for preserving muscle, improving metabolic health, and using GLP-1 medications as part of a broader, sustainable approach to health rather than a standalone solution.
What We Cover
- What GLP-1 medications are and how they work
- The science of food noise, hunger, and appetite regulation
- Why obesity isn’t simply a matter of discipline or willpower
- How genetics, the brain, and the food environment influence body weight
- Differences between semaglutide, tirzepatide, and emerging oral GLP-1 medications
- The importance of protein, resistance training, and preserving muscle while losing weight
- Why Mediterranean-style eating remains important alongside GLP-1 therapy
- Common side effects, dosing strategies, and who may benefit most from these medications
This episode aims to provide a balanced, evidence-based overview of one of the biggest developments in metabolic health. Whether you’re considering a GLP-1 medication yourself, treating patients, or simply trying to understand the science behind the headlines, I hope this conversation gives you the context you need to make more informed decisions.
- Why Terry Simpson Started Taking a GLP-1 (00:00)
- What Is Food Noise, Really? (04:59)
- Why GLP-1 Drugs Work So Well (10:16)
- What Actually Causes Obesity (17:37)
- How GLP-1 Medications Work in the Body (21:22)
- The Strange Lizard Behind GLP-1 Drugs (25:56)
- 3 Types of Hunger You Didn’t Know About (28:41)
- How to Naturally Boost Fullness Signals (37:08)
- How Doctors Choose Which GLP-1 to Prescribe (45:10)
- Why Some People Don’t Respond to GLP-1s (53:09)
- GLP-1 Side Effects, Guilt, and Eating Right (58:12)
- Mediterranean Diet’s Effect on Long-Term Weight Loss (01:10:29)
- The Shame Around Taking GLP-1 Medications (01:20:00)
- Being Called a Pharma Shill (01:32:39)
- The History Behind GLP-1 Drugs (01:38:18)
- Will You Need GLP-1s Forever? (01:47:04)
Resources and links:
- Weight Loss Surgeon: The Science of Food Cravings, Hunger & Weight Loss | Dr Terry Simpson | EP#421
- Nutrition Scientist Dr. Federica Amati: Why It’s So Hard to Lose Weight and Keep It Off
- Obesity Doctor: How to Lose Weight and Reverse Metabolic Disease in 2026 | Dr. Mau
- The Metabolic Syndrome Puzzle: Connecting Diabetes, Obesity, and Liver Disease
- The Brain and Obesity: Are We Wired to Eat More?
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More about Dr Federica Amati
Dr Federica Amati is the Head Nutritionist at ZOE, the nutrition science company leading the gut health revolution, and holds a PhD in Clinical Medicine Research from Imperial College London. She has a masters in Public Health and is an Association for Nutrition (AfN) Registered Nutritionist.
Federica is the author of *Recipes for a Better Menopause,* Sunday Times Bestseller Every Body Should Know This, and *The Appetite Reset.* Her approach focuses on improving overall dietary quality throughout the life course, using food as the best tool to transform health.
More about Dr Mauricio Gonzalez
Dr Mauricio Gonzalez is a triple board certified physician (internal, emergency and obesity medicine) and current endocrinology fellow at Metropolitan Hospital, who practices medicine in New York City who is regarded as one of the most trusted sources of medical information. Dr Gonzalez has been actively promoting prevention strategies in national TV interviews and leveraging the power of social media to debunk myths and share facts related to all things science. For his communication work within the Latino community, he received the Hispanic star award in 2021. He is an active member of multiple efforts that try to shape the next generation of leaders in the USA.
Dr Mau, as he is affectionately known, is passionate about inspiring, motivating and educating his vast online community, medical students and residents about evidence based nutrition and exercise in order to prevent the most common chronic degenerative diseases such as diabetes, hypertension and heart disease. Reaching millions on social media daily, his main mission is to make scientific and medical knowledge available and easy to understand to everyone.
Along with his wife, Mayte Moncada, they’re founders of one of the largest healthy nutrition medical conference in Latin America and for Spanish speakers in the U.S. They have an online academy that might offer classes to more than 27,000 people. He specializes in health communication and collaborate with international industries to curate powerful messages about healthcare that people can actually understand. His work is all about making successful campaigns that truly impact the lives of patients.
He is a regular contributor for CNN, Telemundo, Televisa, Univision and has been featured in Forbes, Newsweek, The Today Show, People Magazine, InStyle, to name a few. An avid public speaker, he has shared a panel with Dr Tedros and Bill Clinton in the patient safety symposium and has been invited to participate in panels with PAHO/WHO, Secretary Becerra, the second gentleman and in the United Nation, among others.
More about Dr Terry Simpson
Dr Terry Simpson is a surgeon with a background that spans molecular biology, critical care, and nutrition. He began his career as a research scientist working in molecular biology, manipulating viral DNA, before pursuing medicine. He trained at the University of Chicago and completed his residency at Virginia Mason in Seattle, where he developed a strong interest in surgery. His surgical career has included trauma and vascular work in the ICU, before transitioning into weight loss surgery.
While working with bariatric patients, Terry became increasingly interested in the role of nutrition, particularly the lack of a standardised dietary approach following surgery. This led him to become certified in Culinary Medicine at Tulane, and to focus more deeply on dietary patterns such as the Mediterranean and DASH diets. During the COVID-19 pandemic, his early background in virology became relevant again as he returned to ICU work and began speaking publicly about virology on social media. He is also a GLP-1 patient himself, having lost 50 pounds and maintained that weight loss while continuing to follow a Mediterranean-style diet. Today, much of his work involves debunking myths, educating people about nutrition, and sharing practical cooking content through his podcast The Unfiltered MD, his Substack, and his social channels.
Outside of his professional life, he is a father to a 15-year-old.
More about Christos Mantzoros
Christos S. Mantzoros, MD, DSc, PhD h.c. mult., is a Professor of Medicine at Harvard Medical School and an Adjunct Professor at Chobanian and Avedisian School of Medicine. He has also served as a Professor of Environmental Health at the Harvard School of Public Health. He currently serves as the Chief of Endocrinology, Diabetes and Metabolism at the Boston VA Healthcare System and the Director of the Human Nutrition Unit of the Division of Endocrinology Diabetes and Metabolism at Beth Israel Deaconess Medical Center. Dr. Mantzoros has been the editor of two books (one on “Diabetes and Obesity” and one on “Nutrition and Metabolism” with more than two editions each). His research has resulted in more than 800 publications in Medline, including more than 150 publications under the collaborative Look Ahead Research Group, more than 200 chapters and reviews, with more than 72,000 citations with a Hirsch Index H=121.
Dr. Mantzoros is also the director for the VA Boston Healthcare System fellowship program with Boston University Medical Center (BUMC), which offers one dedicated fellowship position through BUMC, but also allows any fellow at BUMC or Harvard affiliated fellowship programs the opportunity to rotate through the VA Boston Healthcare System. He has served as a Board Member or an advisor or head of the Scientific Advisor Board of non for profit foundations as well as governmental and non-governmental entities. He is the Editor-in-Chief of the journal Metabolism and is on the editorial board of several scientific journals worldwide. For his research discoveries and public health service Dr. Mantzoros has received four honorary PhDs, the Alexander Technological Institute of Thessaloniki has named their nutrition laboratories after his name and several Universities worldwide have awarded Dr. Mantzoros honorary Professorships and visiting Professorships.
He has or is supervising PhD thesis work in several nations worldwide (Sweden, Germany, Greece, USA etc) and is actively collaborating with many research groups worldwide. He has mentored more than 160 young scientists who currently hold key positions in clinical medicine, academia, industry as well as governmental agencies and nongovernmental organizations. Dr. Mantzoros has been elected a member of ASCI and a Fellow of the American College of Physicians and the American Association of Clinical Endocrinology. He has been given several awards including but not limited to awards by: the American Association of Clinical Endocrinology (Frontiers in Science Award), the American Diabetes Association (Novartis Award in Diabetes and Metabolic Diseases), the North American Association for the Study of Obesity / the Obesity Society (Lilly Award), the American Society for Nutrition (Mead Johnson Award), the HypoCCS award in Paris, France, the Humboldt Foundation of Germany (the Wilhelm Friedrich Bessel Award), by the American Federation of Medical Research (the Outstanding Investigator Award), by the American Physiological Society (FASEB, the Berson Award Lecture), by the New England Hellenic Medical and Dental Association (Hygeia award) etc. He has also received the BIDMC, Harvard Medical School, award for excellence in Mentoring. He will be receiving the 2018 European Society of Endocrinology Geoffrey Harris Prize.
More about Stephan J. Guyenet
After completing a BS in biochemistry at the University of Virginia, Stephan completed a PhD in neuroscience at the University of Washington, then went on to study the neuroscience of obesity and eating behavior as a postdoctoral fellow. He has spent a total of 12 years in the neuroscience research world studying neurodegenerative disease and the neuroscience of body fatness. His publications in scientific journals have been cited more than 4,400 times by his peers. His book, The Hungry Brain, was named one of the best books of the year by Publishers Weekly and called “essential” by The New York Times Book Review. He is the founder and director of Red Pen Reviews, a nonprofit that publishes free expert reviews of popular nutrition books.
