Is there a built-in "fat switch" in our genes—something nature designed to help us store fat for survival? And if so, what does that mean for food addicts living in a world saturated with ultra-processed food? In this episode, Dr. Vera Tarman sits down with Dr. Richard Johnson, Professor Emeritus at the University of Colorado, former Chief of the Division of Renal Diseases and Hypertension, author of The Sugar Fix, The Fat Switch, and Nature Wants Us to Be Fat, and a researcher with 700+ scientific papers to his name. Dr. Johnson explains how fructose (from sugar and high-fructose corn syrup—but also produced inside the body under certain conditions) can activate a powerful metabolic pathway that increases hunger, lowers cellular energy, and shifts calories toward fat storage. He connects this to uric acid, salt, high-glycemic carbohydrates, and the modern "perfect storm" of ultra-processed foods engineered to intensify cravings. Together, they explore the evolutionary logic of fat storage, why visceral fat may have had survival value, why "calories in/calories out" fails to explain the whole picture, and what practical steps can help people restore metabolic flexibility—including carbohydrate reduction, movement that supports mitochondrial health, and the emerging role of GLP-1 medications as a tool (not a replacement) for nutrition change. What You'll Learn 🔥Why Dr. Johnson argues sugar isn't "just a calorie," and how fructose changes metabolism differently 🔥The role of uric acid in blood pressure, metabolic disease, and the fructose pathway 🔥How salt + starch + fat can amplify the "fat switch" (and why chips and fries are a perfect example) 🔥Why the body can make fructose from glucose, even if you aren't eating fructose directly 🔥The survival biology behind fat storage—and why visceral fat may have had an adaptive purpose 🔥How insulin resistance can be a short-term protective mechanism (and how modern life turns it chronic) 🔥Why low-carb approaches may "reboot" sugar absorption and cravings in as little as 7–14 days 🔥What Dr. Johnson believes is a major dietary driver of Alzheimer's risk 🔥How to support mitochondria through movement and nutrition 🔥Dr. Johnson's perspective on GLP-1s: benefits, limits, and relapse risk after stopping Resources Mentioned Dr. Richard Johnson's books: The Sugar Fix, The Fat Switch, Nature Wants Us to Be Fat About Our Guest Dr. Richard Johnson is Professor Emeritus at the University of Colorado, a former Chief of Renal Diseases and Hypertension, and the author of The Sugar Fix, The Fat Switch, and Nature Wants Us to Be Fat. His research explores how sugar—particularly fructose—drives kidney disease, hypertension, diabetes, and obesity, and how modern food environments may overactivate ancient survival pathways. If this episode helped you understand your cravings or your biology with more clarity and less shame, please share it with a friend, leave a review, and subscribe so more people can find recovery-focused science. ✉️ Email us: foodjunkiespodcast@gmail.com Follow us on YouTube: https://www.youtube.com/@FoodJunkiesPodcast The content of our show is educational only. It does not supplement or supersede your healthcare provider's professional relationship and direction. Always seek the advice of your physician or other qualified mental health providers with any questions you may have regarding a medical condition, substance use disorder, or mental health concern.