A Calorie Deficit cannot EVER exist – here’s why!

Jason Fung September 9, 2025
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Jason Fung

@drjasonfung

About

Scientific videos on how to lose weight and reverse type 2 diabetes with diets and intermittent fasting.. Official channel of Dr. Jason Fung - specialist physician, nephrologist and New York Times best selling author of The Obesity Code, The Complete Guide to Fasting, The Diabetes Code and The Cancer Code. Dr. Fung has experience from treating thousands of patients over many decades and shares his insights on weight loss, diets, nutrition, type 2 diabetes reversal, and intermittent fasting. The success rate of basic weight loss advice of calorie counting has been shown to be abysmally low. To lose weight, don't follow strategies that have been proven to fail. Instead, Dr. Fung focuses on understanding the science of calories, diets and fasting as well as practical tips and regimens. He shares patient stories, photos and actual regimens (with permission). To start losing weight and getting healthier, subscribe and hit the bell for notification.

Video Description

Most people are told that “weight loss = calorie deficit.” But the truth is, a calorie deficit is a myth. Your body is not a simple calculator where you just subtract calories and lose fat. In this video, Dr. Jason Fung explains the science behind why focusing only on calories fails, and why hormones, insulin, and fat metabolism are the real keys to healthy and lasting weight loss. When people try extreme dieting or drug-induced appetite suppression, they often experience side effects like the dreaded “Ozempic face” — hollow cheeks, sagging skin, and an unhealthy look. This happens because subcutaneous fat (the fat under the skin) gets burned instead of visceral fat (the dangerous fat around your organs). The result: you may lose weight, but you don’t look or feel healthy. Fasting works completely differently. Instead of just cutting calories, fasting changes your hormones and metabolism: �� Insulin drops, allowing fat burning to start �� Growth hormone rises, protecting muscle and skin elasticity �� Autophagy activates, repairing tissues and preventing loose skin �� Visceral fat is targeted, which improves health and appearance �� Brown fat (through beiging) is activated, boosting metabolism naturally That’s why people who fast look healthier, stronger, and younger compared to those who follow harsh calorie-restricted diets. In this video you’ll discover: ✅ Why calorie restriction almost always fails ✅ The science of subcutaneous vs. visceral fat ✅ How fasting avoids the “Ozempic face” problem ✅ The role of hormones in fat burning and aging ✅ How fasting improves skin health, prevents sagging, and supports long-term fat loss �� If you’re serious about losing weight without losing your health or youthfu look, this video is a must-watch. �� Subscribe now for more science-backed videos on fasting, weight loss, an metabolic health. And don’t forget to like ��, comment ��, and share this vid with anyone who still believes in the calorie deficit myth! ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ ⏱️ Chapters / Timestamps 0:00 – Introduction: Why “calorie deficit” is a myth 1:10 – The calorie counting problem explained 2:30 – How calorie restriction affects your body 3:45 – Subcutaneous vs. visceral fat: which one really matters? 5:20 – Why fasting is different from dieting 6:40 – Hormonal impact: insulin, growth hormone & fat burning 8:00 – Fasting and skin health (no sagging, no hollow cheeks) 9:25 – Autophagy and natural skin tightening 10:45 – White fat vs. brown fat (the beiging effect) 11:50 – Key takeaway: Why calorie deficit cannot ever exist ============================= �� BOOKS: �� The Obesity Code - Reviewing underlying physiology of weight loss an how low carb diets and fasting can help. https://www.amazon.com/dp/1771641258?... �� The Diabetes Code - Reviewing how type 2 diabetes is a reversibl disease and dietary strategies. https://www.amazon.com/dp/B0795BLS8D?... �� The Cancer Code - Scientific exploration of how cancer develops https://www.amazon.com/dp/0062894005?... �� Amazon: �� USA - https://www.amazon.com/shop/jasonfung �� Canada - https://www.amazon.ca/shop/jasonfung ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ �� Please visit our :- �� Website - https://www.doctorjasonfung.com �� Blog- / drjasonfung �� Community- https://www.thefastingmethod.com �� Facebook - / jason.fung.313 �� Instagram - / drjasonfung �� Twitter - / drjasonfung ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ �� YouTube Medical Lectures (for specialist physicians) ▶️ The Roots of the Obesity Epidemic: https: // • The Obesity Epidemic, Explained ▶️ Therapeutic Fasting - The Two Compartment Problem:https: // • Fasting and Weight Loss - Solving the... ▶️ Does Calorie Counting work?: • Why Calorie Counting rarely leads to ... ▶️ Two Big Lies of Type 2 Diabetes: • Two Big Lies about Type 2 Diabetes ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ If you liked the video, Please Do Subscribe My Channel ���� Keep Supporting me So I can Continue to provide you with free content each week!!�� ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ �� �� Thank you for Watching #Fasting #FastingMimickingDiet #DrJasonFung #WeightLoss #IntermittentFasting #FastingForWomen

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