#242: How to Use Intermittent Fasting to Lose Weight, Live Longer, and Feel Better with Dr. Jason Fung

Caloric Model

The traditional calorie-based model of dieting is fundamentally flawed, according to Jason Fung. He argues that calories are not equal because the body's hormonal response to different foods varies significantly. For instance, 100 calories from cookies and 100 calories from eggs trigger different hormonal reactions, leading to different metabolic outcomes 1. Dhru Purohit highlights that the calorie in, calorie out model is deeply ingrained in society, despite being based on shaky science 2. This model fails to consider the body's complex physiological processes, which are not as straightforward as physics in a vacuum 3.

   

Metabolic Rate

Jason Fung explains that reducing calorie intake often leads to a decrease in metabolic rate rather than fat loss. When people cut calories, their bodies adapt by burning fewer calories, which can halt weight loss and lead to feelings of fatigue and coldness 4. This adaptation is why many people regain weight despite maintaining a calorie deficit 5. Fung emphasizes that the simplistic equation of body fat as calories in minus calories out ignores the body's adaptive mechanisms, which have been understood for over a century 6.

It's not a failure of willpower. They're still doing that diet, right?

--- Jason Fung