The Obesity Code Cookbook. Jason Fung

easily caught themselves. If they

      were too skinny, they would not be able to survive the lean times. Body

      fatness is a critical determinant of species survival.

      Figure 3: Weight Gain or Loss Depends Upon the Hormone Insulin

      As such, we rely on hormones to precisely and tightly regulate body

      fat. We don’t consciously control our body weight any more than we

      control our heart rate or body temperature. These are automatically reg-

      ulated, and so is our weight. Hormones tell us we are hungry (ghrelin).

      Hormones tell us we are full (peptide YY, cholecystokinin). Hormones

      increase energy expenditure (adrenalin). Hormones shut down energy

      expenditure (thyroid hormone). Obesity is a hormonal dysregulation of fat

      Fed State

      Storing Food Energy

      Burning Food Energy

      Fasted State

      Eat Food

      Increase

      Insulin

      Store Sugar in Liver

      Produce Fat in Liver

      Burn Stored Sugar in Liver

      Burn Fat in Liver

      Decrease

      Insulin

      No Food

      “Fasting”

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      THE OBESITY CODE COOKBOOK

      accumulation. We get fat because we’ve given our body the hormonal sig-

      nal to gain body fat. The main hormonal signal is insulin, and that level

      goes up or down according to our diet.

      Insulin levels are almost 20 percent higher in obese people compared

      to people within their healthy weight range, and these elevated levels

      are strongly correlated to important indices such as waist circumference

      and waist:hip ratio. Does that mean high insulin causes obesity?

      The “insulin causes obesity” hypothesis is easily tested: If you give

      insulin to a random group of people, will they gain fat? The short answer

      is an emphatic yes. Patients who use insulin regularly and physicians

      who prescribe it already know the awful truth: the more insulin you give,

      the more obesity you get. Numerous studies have demonstrated this fact.

      Insulin causes weight gain.

      The landmark 1993 Diabetes Control and Complications Trial com-

      pared a standard dose of insulin to a high dose designed to tightly

      control blood sugars in patients with type 1 diabetes. Large insulin

      doses controlled blood sugars better, but what happened to the partic-

      ipants’ weight? Participants in the high-dose group gained, on average,

      9.8 pounds (4.5 kilograms) more than participants in the standard group.

      More than 30 percent of the patients experienced “major” weight gain!

      Prior to the study, both groups were more or less equal in weight, with

      little obesity. The only difference between the groups was the amount of

      insulin administered. More insulin resulted in more weight gain.

      Insulin causes obesity. As insulin levels go up, the body set weight

      goes up. The hypothalamus in the brain sends out hormonal signals to

      the body to gain weight. We become hungry and eat. If we deliberately

      restrict our caloric intake in response to this signal, our total energy

      expenditure will decrease. The result is the same: weight gain.

      Once we understand that obesity is a hormonal imbalance, we

      can begin to treat it. Since too much insulin causes obesity, treatment

      demands that we lower insulin levels. The question is not how to balance

      calories but how to balance insulin, our main fat-storing hormone.

      ( 17 )

      introduction

      Insulin levels increase in two circumstances:

      1. We eat more foods that stimulate insulin. Or,

      2. We continue to eat the same insulin-stimulating foods, but more

      frequently.

      Goals

      The Obesity Code laid out the science behind weight gain and how to

      apply that knowledge to lose weight. It forms the theory behind the

      IDM program’s many successes over the years. In this cookbook, I hope

      to make following the principles behind the IDM program even easier to

      implement in day-to-day life by providing simple, delicious recipes and

      meal plans.

      The key to long-lasting weight control is to control the main hor-

      mone responsible, which we’ve established is insulin. There are no drugs

      to control insulin. Controlling insulin requires a change in our diet. This

      boils down to two simple factors: how high insulin levels are after meals,

      and how long they persist.

      1. What we eat determines how high insulin spikes.

      2. When we eat determines how persistent insulin is.

      Most diets concern themselves with only the first factor and there-

      fore fail over the long term. It is not possible to address only half the

      problem and achieve total success. Therefore, this is not a low-calorie

      diet. This is not a low-fat diet. This is not a vegetarian diet. This is not a

      carnivore diet. This is not even necessarily a low-carbohydrate diet. This

      is a diet designed to lower insulin levels because insulin is the physio-

      logical trigger of fat storage. If you want to lower fat storage, you need to

      lower insulin, and this can be done even with a high-carbohydrate diet.

      History shows us this is true. Many traditional societies have eaten

      carbohydrate-based diets without suffering from rampant obesity. In the

      1970s, before the obesity epidemic, the Irish were loving their potatoes.

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      THE OBESITY CODE COOKBOOK

      The Asians were loving their white rice. The French were loving their

      bread. Even in America, as disco was sweeping the nation and Star Wars

      and Jaws played to packed theaters, people were eating white bread and

      jam. They were eating ice cream. They were eating cookies. They were