The Obesity Code Cookbook. Jason Fung

are two puzzling aspects to this obesity epidemic.

      First, what caused it? The fact that it is both global and relatively

      recent argues against an underlying genetic defect. Exercise as a leisure

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      THE OBESITY CODE COOKBOOK

      activity was largely unheard of in the 1970s. People just didn’t sweat to

      the oldies in that decade. The proliferation of gyms, running clubs, and

      exercise studios was a 1980s phenomenon.

      Second, why are we so powerless to stop it? Nobody wants to be fat.

      For more than forty years, doctors have consistently advised that follow-

      ing a low-fat, calorie-reduced diet is the way to stay lean. Yet the obesity

      epidemic has accelerated relentlessly. From 1985 to 2011, the prevalence

      of obesity in Canada tripled from 6 percent to 18 percent. All the avail-

      able evidence shows that people were desperately trying to cut calories

      and fat and exercise more often. But they weren’t losing weight. The

      only logical answer is that we didn’t understand the problem. Eating too

      much fat and too many calories wasn’t the problem, so cutting the fat

      and calories was not the solution. So, what causes weight gain?

      In the 1990s, I graduated from the University of Toronto and the Uni-

      versity of California, Los Angeles, as a physician and kidney specialist. I

      must confess that I did not have the slightest interest in the treatment

      of obesity. Not during medical school, residency, or specialty training, or

      even as I entered practice. But I wasn’t alone. The same was true for just

      about every physician at that time who had trained in North America.

      Medical school taught us virtually nothing about nutrition, and even

      less about the treatment of obesity. There were hours and hours of lec-

      tures dedicated to the proper drugs and surgery to prescribe to patients.

      I was proficient in the use of hundreds of medications. I was proficient

      in the use of dialysis. I knew all about surgical treatments and indica-

      tions. But I knew nothing about how to help people lose weight—despite

      the fact that the obesity epidemic was already well established and the

      type 2 diabetes epidemic was following closely behind, with all its health

      implications. Doctors just didn’t care about diet. That was what dieti-

      tians were for.

      But diet—and maintaining a healthy weight—is an integral part of

      human health. It’s not just about looking good in a bikini for the sum-

      mer swimming season. If only. The excess weight people were now

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      introduction

      carrying was more than an aesthetic issue—it was largely responsible for

      the development of type 2 diabetes and metabolic syndrome, dramat-

      ically increasing the risk of heart attacks, stroke, cancer, kidney disease,

      blindness, amputations, and nerve damage, among other problems. Obe-

      sity was not some peripheral topic of medicine. I was realizing that it

      was central to most of the diseases I was encountering as a physician—

      and I knew almost nothing about it.

      As a kidney specialist, what I did know was that the most common

      cause of kidney failure, by far, was type 2 diabetes. And I treated patients

      with diabetes exactly as I had been trained to—the only way I knew how—

      with drugs like insulin and procedures like dialysis.

      From experience, I knew that insulin would cause weight gain. Actu-

      ally, everybody knew insulin caused weight gain. Patients were rightly

      concerned. “Doctor,” they would say, “you’ve always told me to lose

      weight. But the insulin you gave me makes me gain so much weight.

      How is this helpful?” For a long time, I didn’t have a good answer for

      them, because the truth was, it wasn’t helpful.

      Under my care, my patients were just not getting healthier. I was sim-

      ply holding their hands as they deteriorated. They were unable to lose

      weight. Their type 2 diabetes progressed. Their kidney disease grew more

      serious. The drugs, surgeries, and procedures weren’t doing any good.

      Why?

      The root cause of the entire problem was the weight. Their obesity

      was causing metabolic syndrome and type 2 diabetes, which then caused

      all their other health problems. Yet almost the entire system of modern

      medicine, with its pharmacopoeia, with its nanotechnology, with all the

      genetic wizardry, was focused myopically on the end problems.

      Nobody was treating the root cause. Even if we treated their kidney

      disease with dialysis, patients were still left with their obesity, type 2

      diabetes, and every other obesity-related complication. We needed to treat

      obesity. Instead, we were trying to treat the problems caused by obesity

      rather than obesity itself. This was the way that I, and virtually every

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      other doctor in North America, had been trained to practice medicine in

      this context. But it was not working.

      Figure 1: Standard Paradigm of Medical Treatment

      When people lose weight, their type 2 diabetes reverses course. Treat-

      ing the root cause of a patient’s type 2 diabetes is therefore the only

      logical solution to addressing this disease. If your car is leaking oil, the

      solution is not to buy more oil and mops to clean up the spilled oil. The

      solution is to find the leak and fix it. As medical professionals, we were

      guilty of ignoring the leak and simply mopping up the mess.

      If we could treat the obesity at the beginning (see figure 1), then

      type 2 diabetes and metabolic syndrome could not develop. You can’t

      develop diabetic kidney disease if you don’t have diabetes. You can’t

      develop diabetic nerve damage if you don’t have diabetes. It seems so

      obvious with hindsight.

      So, I had realized where we were going wrong. The problem was that

      I didn’t