The Diabetes Code. Dr. Jason Fung
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Guidelines for Americans released in 2016 have removed restrictions on total dietary fat in a healthy diet.11)
Similarly, the link between natural, saturated fat and heart disease has been proven false.12 While artificially saturated fats, such as trans fats, are universally accepted as toxic, the same does not hold true for naturally occurring fats found in meat and dairy products, such as butter, cream, and cheese—foods that have been part of the human diet for time beyond memory.
As it turns out, the consequences of this newfangled, unproven, low-fat, high-carbohydrate diet were unintended: the rate of obesity soon turned upwards and has never looked back.
The 1980 Dietary Guidelines spawned the infamous food pyramid in all its counterfactual glory. Without any scientific evidence, the formerly “fattening” carbohydrate was reborn as a healthy whole grain. The foods that formed the base of the pyramid—foods we were told to eat every single day—included breads, pastas, and potatoes. These were the precise foods we had previously avoided in order to stay thin. They are also the precise foods that provoke the greatest rise in blood glucose and insulin.
Figure 1.1. Obesity trends in the U.S. after introduction of the “food pyramid” 13
As Figure 1.1 shows, obesity increased immediately. Ten years later, as Figure 1.2 shows, diabetes began its inevitable rise. Age-adjusted prevalence is still rising precipitously. In 1980, an estimated 108 million people worldwide suffered with diabetes. By 2014, that number had swelled to 422 million.14 Even more concerning is the fact that there seems to be no end in sight.
THE TWENTY-FIRST-CENTURY PLAGUE
DIABETES HAS INCREASED significantly in both sexes, every age group, every racial and ethnic group, and all education levels. Type 2 diabetes attacks younger and younger patients. Pediatric clinics, once the sole domain of type 1 diabetes, are now overrun with an epidemic of obese adolescents with type 2 diabetes.15
This is not merely a North American epidemic, but a worldwide phenomenon, although close to 80 percent of the world’s adult diabetics live in developing nations.17 Rates of diabetes are rising fastest in the low- and middle-income nations of the world. In Japan, 80 percent of all new cases of diabetes are type 2.
Figure 1.2. The rising tide of diabetes in the United States16
China, in particular, is a diabetes catastrophe. In 2013, an estimated 11.6 percent of Chinese adults had type 2 diabetes, eclipsing even the long-time champion, the U.S., at 11.3 percent.18 Since 2007, 22 million Chinese—a number close to the population of Australia—have been newly diagnosed with diabetes. This number is even more shocking when you consider that only 1 percent of Chinese had type 2 diabetes in 1980. In a single generation, the diabetes rate has risen by a horrifying 1160 percent. The International Diabetes Federation estimates that the worldwide rate of diabetes will reach 1 in every 10 adults by the year 2040.19
The problem is not trivial. In the U.S., 14.3 percent of adults have type 2 diabetes and 38 percent of the population has prediabetes, totaling 52.3 percent. This means that, for the first time in history, more people have the disease than not. Prediabetes and diabetes is the new normal. Worse, the prevalence of type 2 diabetes has increased only in the last forty years, making it clear that this is not some genetic disease or part of the normal aging process but a lifestyle issue.
It is estimated that, in 2012, diabetes cost $245 billion in the United States due to direct health costs and lost productivity.20 The medical costs associated with treating diabetes and all its complications are two to five times higher than treating nondiabetics. Already, the World Health Organization estimates that 15 percent of annual health budgets worldwide are spent on diabetes-related diseases. Those numbers threaten to bankrupt entire nations.
The combination of prohibitive economic and social costs, increasing prevalence, and younger age of onset make obesity and type 2 diabetes the defining epidemics of this century. Ironically, despite the explosion of medical knowledge and technological advances, diabetes poses an even bigger problem today than it did in 1816.21
In the 1800s, type 1 diabetes predominated. While almost uniformly fatal, it was relatively rare. Fast-forward to 2016, when type 1 diabetes accounts for less than 10 percent of total cases. Type 2 diabetes dominates and its incidence is growing despite its already endemic nature. Almost all type 2 diabetes patients are overweight or obese and will suffer complications related to their diabetes. Although insulin and other modern medicines can treat blood glucose efficiently, lowering blood glucose alone does not prevent the complications of diabetes, including heart disease, stroke, and cancer—leading causes of death.
That we should have a worldwide epidemic of one of the world’s oldest diseases is a bombshell. Whereas all other diseases, from smallpox to influenza to tuberculosis to AIDS, have been controlled over time, the diseases associated with diabetes are increasing at an alarming rate.
But the question still remains: Why? Why are we powerless to stop the spread of type 2 diabetes? Why are we powerless to stop the spread among our children? Why are we powerless to stop the ravages of type 2 diabetes on our bodies? Why are we powerless to prevent the heart attacks, strokes, blindness, kidney disease, and amputations that accompany it? More than 3000 years after its discovery, why is there no cure?
The answer is that we have fundamentally misunderstood the disease called type 2 diabetes. To design rational treatments that have a chance of success, we must begin again. We must understand the root causes of the disease, or in medical terms, the aetiology. What is the aetiology of type 2 diabetes? Once we understand that, we can begin. Let us begin.
THE DIFERENCES BETWEEN TYPE 1 AND TYPE 2 DIABETES
DIABETES MELLITUS COMPRISES a group of metabolic disorders characterized by chronically elevated blood glucose, or hyperglycemia. The prefix hyper means “excessive,” and the suffix emia means “in the blood,” so this term literally means “excessive glucose in the blood.”
There are four broad categories of diabetes mellitus: type 1, type 2, gestational diabetes (high blood glucose associated with pregnancy), and other specific types.1 Type 2 diabetes is by far the most common, making up an estimated 90 percent of cases. Gestational diabetes, by definition, is not a chronic disease, though it increases the future risk of developing type 2 diabetes. If hyperglycemia persists after pregnancy, it must be reclassified as type 1, type 2, or another specific type. Other specific types of diabetes, listed in Table 2.1, are rare. We will not discuss these types of diabetes or gestational diabetes any further in this book.
Table 2.1 Classifications of diabetes mellitus
| Type 1 |
| Type 2 |
| Gestational |
| Other specific types: |
| - Genetic defects |
| - Pancreatic disease |
| - Drug or chemical induced |
| - Infections |
| - Endocrinopathies |
DIABETES