Have you ever counted calories before?
What’s one small change you’d like to make in how you eat?
Today, Jay invites geneticist and author Giles Yeo to challenge one of the most persistent beliefs in modern health culture: the idea that all calories are created equal. Giles is a professor at the University of Cambridge, specializing in the study of how genes influence appetite and body weight. He is the author of Gene Eating and Why Calories Don’t Count, both of which challenge conventional diet myths through the lens of cutting-edge science. Giles is also a science communicator and host of the podcast Dr. Giles Yeo Chews the Fat, where he breaks down complex nutritional concepts with clarity and humor.
Jay begins by asking the question on everyone’s mind—do calories really count? Giles, with a calm and science-grounded approach, unpacks why the answer isn’t so simple. While calorie counting has become a cornerstone of dieting, he explains that the way our bodies extract and process calories depends heavily on the quality of the food, not just the number printed on a label.
Giles shares how our genetic makeup influences hunger, satiety, and fat storage in ways that most diet plans fail to consider. Jay and Giles explore the emotional and social layers of eating, diving into how cultural conditioning, access to healthy food, and even marketing affect our food choices. They also examine why it's harder for some people to lose weight than others—not because of laziness or lack of willpower, but because their biology is wired differently. Giles challenges the shame-based narratives around body weight and reframes the discussion around health, sustainability, and self-awareness.
In this interview, you'll learn:
How to Eat for Quality, Not Just Calories
How to Read Food Labels the Right Way
How to Choose Protein, Fiber, and Sugar Wisely
How to Spot Diet Myths That Don’t Serve You
How to Lose Weight Without Obsessing Over Numbers
How to Understand Your Body’s Unique Metabolism
How to Manage Cravings with a Plan, Not Willpower
You don’t need to follow a strict diet or obsess over every calorie to feel better in your body. Instead, focus on nourishing yourself with real, quality foods, making small sustainable changes, and understanding how your unique biology works.
With Love and Gratitude,
Jay Shetty
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What We Discuss:
00:00 Intro
02:54 Do Calories Actually Matter?
03:33 Why Protein Makes Your Body Work Harder
05:12 Are You Eating More Than You Think?
07:05 Why Food Quality Matters More Than Quantity
07:56 How Processing Increases Calorie Absorption
11:04 What Really Makes Food Healthy?
12:00 When Did Obesity Become a Global Crisis?
12:52 How Fast Food Became the Default
15:05 The Real Impact of Unhealthy Weight Gain
17:45 The Macronutrients You’re Missing Out On
20:08 Are You Absorbing the Nutrients You Eat?
22:58 How Cutting Ultra-Processed Foods Affects Weight
24:59 Does Better Flavor Mean More Nutrition?
26:32 Why We Process Calories Differently
29:45 Can You Actually Target Belly Fat?
30:54 How Genetics Influence Your Body Shape
32:06 Are You Limited by Your Genes?
34:55 How to Adjust Your Diet for Real Change
38:14 The Smart Way to Read a Nutrition Label
40:53 Fried vs. Baked: What's the Healthier Option?
41:51 What Is 'Incidental Virtuous Food'?
44:52 Is Orange Juice as Healthy as You Think?
47:32 How Food Labels Can Be Misleading
49:24 The Truth About Protein Bars
51:07 3 Things to Focus on When Reading Labels
52:45 The Hidden Ingredients to Watch For
55:56 Why Weight Is About Biology, Not Willpower
58:39 Do You Really Lack Willpower?
59:11 How to Outsmart Your Cravings
01:01:29 Why “Out of Sight, Out of Mind” Works
01:04:06 Do Not Neglect Your Health as You Age
01:07:12 What You Need to Know About Appetite-Suppressing Drugs
01:11:02 The Hidden Risks of Weight Loss Medications
01:12:33 2 Truths Everyone Should Know About Healthy Eating
01:13:58 Start With This: Protein, Fiber, and Sugar
01:15:55 Giles on Final Five
Episode Resources:
Dr. Giles Yeo | Instagram
Dr. Giles Yeo | Facebook
Dr. Giles Yeo | LinkedIn
Dr. Giles Yeo | X
Gene Eating: The Story of Human Appetite
Why Calories Don't Count: How We Got the Science of Weight Loss Wrong
See omnystudio.com/listener for privacy information.
On Purpose with Jay Shetty 
