Chapter 6: A New Hope

Jul 19, 2019


Click here to watch a replay of the Facebook LIVE discussion. 

You Will Learn

  • A hormonal (vs the traditional caloric) theory for obesity.  
  • How macronutrients (carbohydrates, proteins, and fats) affect insulin levels.  
  • How insulin levels affect fat creation and storage (i.e. your body set weight).  


About Dr. Fung, Author of The Obesity Code and The Diabetes Code

Dr. Jason Fung is a medical doctor, nephrologist by trade, who specializes in kidney disease, type 2 diabetes, and obesity. He acknowledged that traditional medicine wastes time and resources attempting to treat symptoms of disease, rather than the cause of disease.  

You can purchase The Obesity Code book HERE. Most information in this post is direct from this book. 


Overview of the Book

Here is an outline of the book. Today I’m covering Chapter 6 in Part 3 of the book. 

  • Part 1: “The Epidemic,” explores the timeline of the obesity epidemic and the contribution of the patient’s family history. It highlights the underlying causes of obesity. 
  • Part 2: “The Calorie Deception,” reviews the current caloric theory in depth and highlights the shortcomings of the current understanding of obesity. 
  • Part 3: “A New Model of Obesity,” describes how hormones are involved in the development of obesity. These chapters explain the central role of insulin in regulating body weight and describe the vitally important role of insulin resistance. 
  • Part 4: “The Social Phenomenon of Obesity,” dives into childhood obesity and why obesity is associated with poverty. 
  • Part 5: “What’s Wrong with Our Diet?,” explores the role of fat, protein, and carbohydrates, the three macronutrients, in weight gain. In addition, it examines one of the main culprits in weight gain - fructose - and the effects of artificial sweeteners. 
  • Part 6: “The Solution,” provides guidelines for lasting treatment of obesity by addressing the hormonal imbalance of high blood insulin through proper nutrition, sleep, and stress management. 


A Hormonal Theory for Obesity 

As Dr. Fung describes, (and a lot of research and empirical evidence suggests), the caloric-reduction model for treating obesity was just wrong. Excess calories did not cause obesity, so reducing calories could not cure it. Lack of exercise did not cause obesity, so increased exercise could not cure it.  

There is not a single cause of obesity. Many of the current theories about what causes obesity like excess carbohydrates, poverty, low fiber intake, and snacking, all contain some partial truth, especially in light of this new hormonal theory of obesity.  

Obesity is a hormonal dysregulation of fat mass. Our body set weight, discussed in Chapter 5, is set too high. In order to effectively treat obesity for the long-run we need to lower our body set weight. Research is showing we do this by focusing on lowering insulin levels.  

"A hormone suspected of causing weight gain must pass the causality test. If we inject this hormone into people, they must gain weight. Two hormones pass this test: cortisol and insulin." p. 72  

Cortisol is also known as your stress hormone. It increases with any type of stress.  

Insulin is also known as your fat creation and storage hormone. It causes sugar to be moved from your bloodstream into your cells.  


How Macronutrients Affect Insulin Levels  

Following the logic that high insulin levels cause obesity, it is important to understand how different macronutrients, or types of food, affect your insulin levels.  

This hormonal theory of obesity explains why certain foods like pop and other sugary foods increase our fat mass and waist line.  

Simply stated, there are three macronutrients that make up our food. Some foods only have one of the three, others contain all three. Those are:

Fats cause a low blood sugar and insulin response. Proteins cause a minimal blood sugar response but do have a moderate insulin response. Carbohydrates, especially refined carbohydrates like those found in processed foods, flours, and added sugar, cause both a high blood sugar and blood insulin response. 

Processed carbohydrates are certainly not the ONLY factor that will lead to obesity, but they are a big culprit. 

For a more in-depth discussion on how carbohydrates affect insulin levels, check out this article I wrote all about sugar. 


How Insulin Levels Affect Fat Creation and Storage 

As I mentioned above, insulin is the hormone that causes sugar to move from your blood into your cells. It is one of the primary hormones involved in fat creation and storage.  

When you eat a meal, especially a typical Western American diet type of meal high in processed and refined carbohydrates, your body is flooded with glucose (AKA blood sugar). Insulin is responsible for moving this sugar out of your bloodstream and into your cells.  

But there is more energy than your body needs at one time so it has to find ways to store the extra glucose. The first thing that happens is extra glucose stored as glycogen in your liver. But there is only so much room in your liver, so the rest of the glucose is turned into fat.  

Dr. Fung gives a great analogy in his book relating this to money in your wallet and bank account on page 75.  

Think of money as glucose. Your wallet as glycogen. Your bank account as fat stores.  

“Glycogen is like your wallet. Money goes in and out constantly. The wallet is easily accessible, but can only hold a limited amount of money. Fat, however, is like the money in your bank account. It is harder to access that money, but there is an unlimited storage space for energy there in your account. Like the wallet, glycogen is quickly able to provide glucose to the body. However, the supply of glycogen is limited. Like the bank account, fat stores contain an unlimited amount of energy, but they are hard to access.”  


Bottom Line 

  • Obesity is not caused by eating too many calories. Research has shown that eating more quality, nutritious food won’t make you fat. Eating foods, especially a lot of foods that cause a high insulin release contribute to the development of obesity. In other words, calories mean very little without the effect they have on insulin levels. 
  • Carbohydrates, especially refined and processed carbohydrates, cause the highest insulin release of all three macronutrients. Next is protein, then fat.  
  • High insulin levels encourage sugar and fat storage. Low insulin levels encourage sugar and fat burning.   



1. Chapter 6. (2016). In J. Fung, The Obesity Code: Unlocking the Secrets of Weight Loss. Vancouver: Greystone Books.

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