Why 72 Hours Changes Everything: The Science of Fasting, Autophagy & Cellular Reset

About this episode: In this episode of the Thrive with Cate Stillman Podcast, Cate leads a live Club Thrive session recorded mid-fast alongside members deep in their own 72-hour water fast or Fast Mimicking Diet (FMD) cycles — delivering one of the most scientifically rich and practically grounded conversations in the series. Cate walks through a research-backed slide deck — built with AI and Perplexity — that maps exactly what happens inside your liver, cells, and brain from hour zero to hour 72 of a fast. From the sharp insulin drop at hour 12 to the ketogenesis threshold at hour 18, through to peak autophagy and mitochondrial pruning at hours 48 to 72, this session makes the invisible visible. She explains why beta-hydroxybutyrate (BHB) — the primary ketone body produced during fasting — is not just fuel for the brain, but a powerful signaling molecule that regulates gene expression, reduces inflammation, and suppresses appetite. She also presents clinical trial data showing that three FMD cycles can reduce liver fat by nearly 50% — and connects all of it back to Ayurvedic frameworks around liver health, Kapha-Pitta imbalance, and the ancient concept of internal surgery through fasting. Beyond the science, this session explores the cultural conditioning around food, why hunger resistance is often inherited rather than biological, and how to use the fasted state as a window for deep mental and emotional processing. Key Takeaways: The Liver Timeline: What happens hour by hour — glycogen depletion, glucagon rise, AMPK activation, ketogenesis, and peak autophagy BHB Explained: Why the brain runs better on ketones than glucose — and why this only happens when glycogen stores are fully depleted Autophagy in Action: How lysosomes engulf and upcycle damaged cells, misfolded proteins, and senescent tissue FMD & Fatty Liver: Clinical evidence showing measurable reductions in liver fat and fibrosis markers across FMD cycles Cultural Fasting Resistance: Why most resistance to extended fasting is inherited from food culture — not biology Fasting as Mental Clarity: How the fasted state slows down habitual patterns, surfaces emotional triggers, and creates space for deep self-study Resources & Links: Wellness Pro Academy: https://wellnesspro.academy Yogahealer: https://www.yogahealer.com Gut Health Challenge: https://guthealthchallenge.scoreapp.com About the Host – Cate Stillman: Cate Stillman is an Ayurvedic practitioner, author, and founder of Yogahealer and Wellness Pro Academy. For over 25 years, she has guided wellness professionals and individuals to align their habits, health, and business with natural intelligence and sustainable practices.