Jason Fung

Why Do We get Fat? Part 1 - The Biggest Lie in Obesity Medicine

Jason Fung

Summary

Weight gain is often attributed to calorie consumption, but recent insights challenge this conventional wisdom. The discussion emphasizes that calories alone do not cause obesity; rather, hormonal factors play a crucial role in regulating body fat. Insulin, a key hormone, signals the body to store fat, influencing hunger and satiety. When insulin levels are high, individuals may feel hungrier, leading to increased food intake, which perpetuates weight gain.

The conversation also critiques the simplistic view of weight loss as merely a matter of eating less and exercising more. It argues that reducing calorie intake can lead to a decrease in basal metabolic rate, meaning the body burns fewer calories, which can counteract weight loss efforts. This highlights the importance of understanding the hormonal responses to different foods, as some foods can trigger more insulin release than others, affecting how the body processes calories.

Ultimately, the discussion advocates for a more nuanced approach to weight management that considers hormonal balance rather than solely focusing on calorie counting. This perspective encourages individuals to think critically about the types of foods they consume and their effects on body fat regulation.

Show Notes

This is Why You're Not Losing Weight (Its Not Calories) | Dr. Jason FungPre-order The Hunger Code - Out March 2026 at www.doctorjasonfung.comVisit www.drinkaeira.com for hunger management tools.Stop counting calories! It's the biggest, most damaging lie in obesity medicine.In this video, Dr. Jason Fung, the best-selling author of The Obesity Code & The Hunger Code dismantles the single biggest myth in weight loss: CaloriesIn, Calories Out (CICO).For decades, we've been told that weight gain is a personal failing—a simple lackof willpower. Dr. Fung explains why this is completely false. He reveals thatweight gain isn't a calorie problem; it's a hormonal problem.In this video you will learn:● Why the CICO equation, while technically true, is practically useless forweight loss.● The problem: Why your Basal Metabolic Rate (BMR)plummets when you cut calories, sabotaging your efforts.● The true Arrow of Causality: Hormones (not calories) are the real causeof weight gain.● How Insulin, the master hormone, forces your body to store fat and makesyou hungrier.● Why 100 calories from a cookie is NOT the same as 100 calories from anegg.● The Circular Logic trap that keeps people fixated on counting.● How food acts as information that gives your body specific instructions.This is a must-watch for anyone who has struggled with yo-yo dieting and islooking for the real, science-based solution to lasting weight loss.�� If you’re serious about losing weight without losing your health or youthfulook, this video is a must-watch.�� Subscribe now for more science-backed videos on fasting, weight loss, anmetabolic health. And don’t forget to like ��, comment ��, and share this vidwith anyone who still believes in the calorie deficit myth!▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬⏱️ Chapters / Timestamps00:00 - The Biggest Lie in Obesity Medicine00:40 - The Flawed Calories In vs. Calories Out Equation01:15 - Why We Think Obesity is a Personal Failing (And Why It's Wrong)02:13 - Body Fat is Tightly Controlled by Hormones03:02 - The Problem: Why Eating Less Fails03:50 - The Inevitable Drop: Basal Metabolic Rate (BMR)04:37 - The Real Cause of Weight Gain: Hormones05:13 - The Master Hormone: How Insulin Makes You Fat06:00 - Hormones Control Your Hunger & BMR (Not Willpower)08:21 - The Circular Logic Trap of CICO08:40 - Not All Calories Are Equal (Cookies vs. Eggs)10:14 - Food is NOT Just Energy, It's Information11:09 - The Critical Choice: Store Calories or Burn Calories?12:12 - Final Takeaway: Focus on Hormones, Not Calories=============================�� BOOKS:�� The Obesity Code - Reviewing underlying physiology of weight loss anhow low carb diets and fasting can help.https://www.amazon.com/dp/1771641258?...�� The Diabetes Code - Reviewing how type 2 diabetes is a reversibldisease and dietary strategies. https://www.amazon.com/dp/B0795BLS8D?...�� The Cancer Code - Scientific exploration of how cancer developshttps://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 2Diabetes▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬If you liked the video, Please Do Subscribe My Channel ����Keep Supporting me S Learn more about your ad choices. Visit megaphone.fm/adchoices

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Oct 27, 2026

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Oct 27, 2026

Cutting Calories Doesn't Work - It's simple Algebra ❌🥗 || Jason Fung || Dr. Jason Fung Explains the Truth About Weight Loss & Insulin!Are you tired of hearing that the secret to weight loss is simply cutting calories? 🧐 Well, in this video, Dr. Jason Fung breaks down why calorie counting has NEVER worked and why it NEVER will! 🚫Let’s talk about the real reason why we gain weight and how calorie cutting can actually backfire. It’s not just about “calories in vs. calories out” – it’s WAY more complex than that. In fact, hormones, especially insulin, play a HUGE role in how your body stores fat! 🔄🍔Key Points Covered:1. Body’s Adaptation: When you cut calories, your body actually fights back by reducing energy expenditure, leading to a weight loss plateau. 😱 This is why calorie restriction alone doesn’t work long-term.2.Role of Insulin: Discover how insulin plays a critical role in weight gain by telling your body to store fat. 🧬💡 It’s not just about calories, it’s about the hormonal balance that shifts the relationship between calories in and calories out.3. Circular Logic of Dieting: You’ve heard it all before: "You’re gaining weight because you’re eating too much," but Dr. Fung explains why this is a classic case of circular logic that doesn’t solve the real issue. 🔄🤔4. The REAL Solution: Instead of focusing on calorie counting, the focus should be on what causes the imbalance – hormones like insulin. Dr. Fung gives insights on how to tackle the ROOT cause of weight gain. 🌿🔑Forget the traditional methods of counting calories and learn how to fix the real problem behind weight gain. 💥 Understanding your body’s hormonal response is the key to lasting weight loss and better health.🔥 Watch the full video to learn why calorie cutting isn’t the answer and how you can lose weight more effectively by focusing on the right things! 🔥If you enjoyed this video, don’t forget to Like, Share, and Subscribe for more health tips and insights from Dr. Jason Fung! 📺👍 ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▶️ Timestamps / Chapters00:00 intro00:03 why calorie counting doesn’t work00:29 energy balance equation01:45 what causes weight gain?03:17 what causes alcoholism?04:49 what changed the ratio of CI to CO?08:30 why does calories In/ calories out seem so intuitive?09:02 outro=============================📌 BOOKS:👉 The Obesity Code - Reviewing underlying physiology of weight loss and how lowcarb diets and fasting can help. https://www.amazon.com/dp/1771641258?...👉 The Diabetes Code - Reviewing how type 2 diabetes is a reversible disease anddietary 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- https://drjasonfung.medium.com🔹 Community- https://www.thefastingmethod.com🔹 Facebook - https://www.facebook.com/jason.fung.313🔹 Instagram - https://www.instagram.com/drjasonfung/🔹 Twitter - https://twitter.com/drjasonfung▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬📌 YouTube Medical Lectures (for specialist physicians):▶️ The Roots of the Obesity Epidemic: https://www.youtube.com/watch?v=q8BGYhreaco&t=0s▶️ Therapeutic Fasting - The Two Compartment Problem: https://www.youtube.com/watch?v=ETkwZIi3R7w&t=0s▶️ Does Calorie Counting work?:https://www.youtube.com/watch?v=5F5o0a4p_3U&t=0s▶️ Two Big Lies of Type 2 Diabetes:https://www.youtube.com/watch?v=FcLoaVNQ3rc&t=0s▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬If you liked the video, Please Do Subscribe My Channel 😉😍Keep Supporting me So I can Continue to provide you with free content eachweek!!😇▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬😍 😍 Thank you for Watching!#CalorieCountingMyth #DrJasonFung #weightlosstips Learn more about your ad choices. Visit megaphone.fm/adchoices

Oct 27, 2026

Check out Aeira powdered bone broth for managing hunger during fasting at www.drinkaeira.comFor decades, we were told to follow the Food Pyramid. We were told to eat 6-11 servings of bread and pasta a day and fear dietary fat. We followed the rules. But instead of getting healthier, the world got sicker and more obese. Why?In this video, I expose the truth behind one of the biggest failures in modern nutrition—the Food Pyramid. We explore how the 1977 dietary guidelines, though well-intentioned, were based on shaky science that demonized healthy fats and promoted insulin-spiking carbohydrates.If you’ve ever felt frustrated because you "ate right" according to the guidelines but still gained weight, this video explains exactly why that happened. It’s time to unlearn the old rules and understand how food actually affects your hormones and metabolic health.In this video, you will discover:● ⚠️ The Great Mistake: How the 1977 guidelines accidentally triggered the obesity epidemic.● 🍞 The Carb Trap: Why the base of the old pyramid (grains) is the primary driver of insulin resistance.● 🥑 The Fat Fear: Why we were taught to fear the wrong nutrient and how healthy fats protect your metabolism.● 🥗 The NEW Solution: A science-backed approach to eating that focuses on hormonal balance, not just calorie counting.Drop a comment below: Did you grow up following the Food Pyramid? How has changing your diet impacted your health? I’d love to hear your story. 👇▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ ⏱️ Chapters / Timestamps00:00 - The Confusion: Why "Eating Right" Made Us Sick 00:45 - The 1977 Disaster: Problems with the Old Food Pyramid 01:40 - The History: Who Created These Guidelines? 02:45 - The Hidden Culprit: Carbohydrates & Insulin Spikes 03:55 - The Low-Fat Myth: Why We Were Wrong About Fat 05:10 - The New Food Pyramid: A Metabolic Approach 06:30 - It’s Not Calories, It’s Insulin (Weight Loss Basics) 07:25 - The "Focus Foods": What You Should Actually Eat 08:05 - Final Thoughts: Taking Control of Your Health============================= 📌 BOOKS: 👉 The Obesity Code - Reviewing underlying physiology of weight loss and how low carb diets and fasting can help. https://www.amazon.com/dp/1771641258?... 👉 The Diabetes Code - Reviewing how type 2 diabetes is a reversible 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! #FoodPyramid #DrJasonFung #InsulinResistance #LowCarb #NutritionMyths #MetabolicHealth #WeightLossJourney #HealthyEating Learn more about your ad choices. Visit megaphone.fm/adchoices

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