Dr. Jason Fung returns to the CrossFit Podcast to unpack the real driver behind weight gain and chronic hunger. Drawing from decades of clinical experience and his new book “The Hunger Code,” Fung challenges the “calorie in, calorie out” model and explains why it has failed so many people for so long.
This conversation goes deeper than macros and meal plans. Fung breaks down the three types of hunger: homeostatic, hedonic, and conditioned. He explains how ultra-processed foods, the modern food environment, and social conditioning override natural appetite regulation. He and host Jocelyn Rylee explore how insulin and other hormones shape body fat regulation, and why long-term success depends on restoring satiety rather than fighting willpower.
Topics Covered
- Why calorie restriction fails long-term.
- The three types of hunger and how they drive overeating.
- How ultra-processed food hijacks appetite and satiety.
- Hormones and the body fat thermostat.
- Social environments and practical levers for change.
Resources Mentioned
- Dr. Jason Fung
- The Hunger Code by Dr. Jason Fung
- The Obesity Code by Dr. Jason Fung\
- Hunger by Roxane Gay
Community Highlight
Travis Ponikiewski doesn’t train for the leaderboard.
He trains because he has two little girls who think he’s invincible, and he plans on keeping it that way for a long time.
When Travis was young, he lost his dad. Now that he’s a father himself, that experience quietly shapes everything. For him, fitness isn’t aesthetic. It’s responsibility. It’s making sure his daughters don’t grow up with missing memories.
At home, that same steadiness shows up in how he supports his wife through mental health struggles. He wants her to feel strong again, on her terms.
He cares less about how his girls look and more about what they’re capable of. Strong bodies. Healthy relationship with food. Confidence that doesn’t shrink to fit the world.
He’s even working toward his Level 1 — not to collect a title, but to better serve the people around him.
Learn More In “The Science of Appetite”
By: Jocelyn Rylee, CF-L4, MS in Human Nutrition
In this installment of our Research Round Up series, we’re taking on the topic of appetite, specifically tackling what we can learn to make how much we want to eat match how much we need to eat.