Watch the full episode and view show notes here: https://bit.ly/3ydzKti Become a member to receive exclusive content: https://bit.ly/3HJBptT Sign up to receive Peter's email newsletter: https://bit.ly/4c602k2 Stephan Guyenet is a neuroscientist focused on the neuroscience of obesity and energy homeostasis.  He is the author of the book, The Hungry Brain and founder/ director of Red Pen Reviews. In this episode, Stephan explains how obesity has changed phenotypically over the course of human history as well as what might explain the dramatic increase in prevalence of obesity in the last few decades. He talks in depth about the role of genetics, the brain, and hormones like leptin play in the regulation of fat mass. He dives deep into two common theories of obesity—the carbohydrate-insulin model and the energy balance model and provides his take on which theory has stronger evidence. Additionally, he provides insights on how we’re hard-wired to think about food and the consequences of modern foods designed for maximal pleasure. Finally, he goes through the factors that affect body weight, set points, and provides takeaways for people wanting to take advantage of what we know about the brain’s role in regulating our body weight. We discuss: 0:00:00 - Intro 0:00:08 - Stephan’s neuroscience background and his focus on the nuances of obesity 0:07:17 - How obesity has changed for humans throughout history 0:14:45 - The association between obesity and adverse health outcomes, the “obesity paradox,” and confounders when relating BMI to longevity 0:25:49 - The sharp increase in obesity across demographics 0:33:52 - The hypothalamus and its role in obesity 0:45:32 - The role of the hormone leptin in obesity 0:53:24 - The genetic component of obesity 1:05:48 - Understanding the tendency of humans to store fat through an evolutionary lens 1:13:32 - The hedonic aspect of food, and how the brain reacts to modern, highly-rewarding foods 1:26:46 - How we are hard-wired to think about food 1:35:16 - A review of the “Carnivore diet” 1:50:06 - The energy balance model, carbohydrate-insulin model, and unifying the theories around adiposity 1:58:41 - Body weight set points: a hypothetical comparison of two individuals 2:07:26 - Takeaways for people who want to lose weight and keep it off 2:16:34 - Evidence that favors the energy balance model of weight gain 2:26:54 - The synergistic effect of fat and carbohydrates and observations that a low-fat diet or a low-carb diet can cause weight loss 2:34:46 - Red Pen Reviews -------- About: The Peter Attia Drive is a weekly, ultra-deep-dive podcast focusing on maximizing health, longevity, critical thinking…and a few other things. With over 45 million episodes downloaded, it features topics including fasting, ketosis, Alzheimer’s disease, cancer, mental health, and much more. Peter is a physician focusing on the applied science of longevity. His practice deals extensively with nutritional interventions, exercise physiology, sleep physiology, emotional and mental health, and pharmacology to increase lifespan (delay the onset of chronic disease), while simultaneously improving healthspan (quality of life). Learn more: https://bit.ly/3OcTzXg Connect with Peter on: Facebook: http://bit.ly/PeterAttiaMDFB Twitter: http://bit.ly/PeterAttiaMDTW Instagram: http://bit.ly/PeterAttiaMDIG Subscribe to The Drive: Apple Podcast: http://bit.ly/TheDriveApplePodcasts Overcast: http://bit.ly/TheDriveOvercast Spotify: http://bit.ly/TheDriveSpotify Google Podcasts: http://bit.ly/TheDriveGoogle Disclaimer: This podcast is for general informational purposes only and does not constitute the practice of medicine, nursing, or other professional healthcare services, including the giving of medical advice. No doctor-patient relationship is formed. The use of this information and the materials linked to this podcast is at the user's own risk. The content on this podcast is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should not disregard or delay in obtaining medical advice for any medical condition they have, and they should seek the assistance of their healthcare professionals for any such conditions. I take conflicts of interest very seriously. For all of my disclosures and the companies I invest in or advise, please visit my website where I keep an up-to-date and active list of such companies.