The NEW Era of Fasting: PSMF vs Water Fasting & The 3 Types of Hunger | Dr. Jason Fung

In this episode, Vanessa is joined by Dr. Jason Fung, author of The Hunger Code, to unpack the hormonal science behind fat loss — and how fasting may be entering a new era.

They start with the three types of hunger and why obesity is not simply about willpower, but disrupted hormonal signaling. We break down insulin's role in fat storage, obesity, and how ultra-processed foods blunt satiety hormones.

Vanessa and Dr. Fung also discuss how protein, fiber, and fat affect hunger very differently than refined carbohydrates — and why a calorie is not metabolically neutral.

Then they shift to fasting. Dr. Fung shares his current protocols and comments on emerging research supporting Protein-Sparing Modified Fasting (PSMF) as a more practical, muscle-conscious alternative to prolonged water fasting.

They cover:

• PSMF vs water fasting

• Protecting lean mass during fat loss

• GLP-1 medications — risks and unintended consequences

• Appetite suppression vs true metabolic health

• Fat loss considerations for women in peri- and post-menopause

This conversation challenges the idea that all fasting approaches are created equal — and reframes modern fat loss through a hormonal lens.

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Protein-Sparing Modified Fasting Library (Coming Soon)

Vanessa shares her behind-the-scenes system built from the approach she used to lose 14+ lbs of body fat while preserving lean mass.

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The content provided in this podcast is for informational purposes only and should not be construed as medical advice. Consult with a healthcare professional before making significant changes to your diet or exercise regimen.