The Hunger Code: Resetting Your Body's Fat Thermostat in the Age of Ultra-Processed Food (The Obesity Code Book 2)

The Hunger Code is the sequel to The Obesity Code by Dr. Jason Fung, a nephrologist and New York Times bestselling author. While The Obesity Code helped people lose weight naturally, The Hunger Code addresses weight loss and maintenance in the modern era of weight-loss drugs and ultra-processed foods, without requiring calorie counting. The book challenges the assumption that weight loss cannot be sustained long-term. Rather than treating weight gain as a symptom, it examines root causes of why people eat. Dr. Fung identifies three forces that drive eating: physical hunger, emotional hunger, and social hunger. He introduces the concept of the body's "fat thermostat"—a biological set point regulated by hormones and metabolism that influences hunger and energy use. The book provides three Golden Rules and 50 actionable tips to help readers recognize and respond to hunger appropriately. Topics include slowing digestion, breaking emotional eating cycles, and managing social pressures to eat. The guidance applies whether someone is starting fresh, returning to eating after fasting, or transitioning after using weight-loss medications.