The Obesity Code Cookbook. Jason Fung

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      Amputation

      Nerve Damage

      ( 14 )

      THE OBESITY CODE COOKBOOK

      not eating. If your body doesn’t count calories, why should you? A calo-

      rie is purely a unit of energy borrowed from physics. The field of obesity

      medicine, desperate for some simple measure of food energy, completely

      ignored human physiology and turned to physics instead.

      “A calorie is a calorie” soon became the statement du jour. It also gave

      rise to a question: Are all calories of food energy equally fattening? The

      answer to that is an emphatic no. One hundred calories of kale salad are

      not as fattening as one hundred calories of candy. One hundred calories

      of beans are not as fattening as one hundred calories of white bread and

      jam. But for the last forty years, we have believed that all calories are

      equally fattening.

      And that’s why I wrote The Obesity Code. In that book, I drew on what

      I learned over ten years of helping thousands of patients lose weight

      through my Intensive Dietary Management program. Nutrition is the

      key to metabolism, the process of breaking down food molecules to

      provide energy (calories) for the body and using that energy to build,

      maintain, and repair body tissues and allow the body to function effi-

      ciently. To answer the all-important question—what are the underlying

      causes of weight gain?—I started at the beginning, unraveled the calories

      model, and explained what’s really going on: Obesity is a hormonal, not

      a caloric, imbalance. And what we eat and when we eat are two major

      influences on our ability to manage weight gain and weight loss.

      Insulin

      In our body, nothing happens by accident. Every single physiological

      process is a tight orchestration of hormonal signals. Whether our heart

      beats faster or slower is tightly controlled by hormones. Whether we

      urinate a lot or a little is tightly controlled by hormones. Whether the

      calories we eat are burned as energy or stored as body fat is also tightly

      controlled by hormones. So, the main problem in terms of obesity is not

      the number of calories we eat, but how they are spent. And the main

      hormone we need to know about is insulin.

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      introduction

      Insulin is a fat-storing hormone. There’s nothing wrong with that—

      that’s simply its job. When we eat, insulin production goes up, signaling

      the body to store some food energy as body fat. When we don’t eat, insu-

      lin production goes down, signaling the body to burn the stored energy

      (body fat). Higher-than-usual insulin levels tell our body to store more

      food energy as body fat.

      Everything about human metabolism, including body weight,

      depends upon hormonal signaling. A critical physiological variable such

      as body fatness is not left up to the vagaries of daily caloric intake and

      exercise. If early humans were too fat, they could not easily run and

      catch prey, and they would be more 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 СКАЧАТЬ