Wheat Belly. William MD Davis
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obese because we’re inactive and gluttonous. We sit on our fat behinds watching too much reality TV, spend too much time online and don’t exercise. We drink too many sugary fizzy drinks and eat too much fast food and too many junk snacks. Betcha can’t eat just one!
Certainly these are poor habits that will eventually take their toll on one’s health. But I meet plenty of people who tell me that they follow ‘official’ nutritional guidelines seriously, avoid junk foods and fast foods, exercise an hour every day, all while continuing to gain and gain and gain. Many follow the guidelines set by the USDA food pyramid (six to eleven servings of grain per day, of which four or more should be whole grain), the American Heart Association, the American Dietetic Association or the American Diabetes Association. The cornerstone of all these nutritional directives? ‘Eat more healthy whole grains’. This largely matches the advice given by the UK government and the NHS, which recommend that you ‘choose wholegrain varieties whenever you can’.
Are these organisations in cahoots with the wheat farmers and seed and chemical companies? There’s more to it than that. ‘Eat more healthy whole grains’ is really just the corollary of the ‘Cut the fat’ movement embraced by the medical establishment in the sixties. Based on epidemiologic observations that suggested that higher dietary fat intakes are associated with higher cholesterol levels and risk for heart disease, Americans were advised to reduce total and saturated fat intake. Grain-based foods came to replace the calorie gap left by reduced fat consumption. The whole-grain-is-better-than-white argument further fuelled the transition. The low-fat, more-grain message also proved enormously profitable for the processed food industry. It triggered an explosion of processed food products, most requiring just a few pence worth of basic materials. Wheat flour, cornflour, high-fructose corn syrup, sucrose, and food colouring are now the main ingredients of products that fill the interior aisles of any modern supermarket. (Whole ingredients such as vegetables, meats and dairy tend to be at the perimeter of these same stores.) Revenues for Big Food companies swelled. Kraft alone now generates $48.1 billion in annual revenues, an 1,800 per cent increase since the late eighties, a substantial portion of which comes from wheat- and corn-based snacks.
Just as the tobacco industry created and sustained its market with the addictive property of cigarettes, so does wheat in the diet make for a helpless, hungry consumer. From the perspective of the seller of food products, wheat is a perfect processed food ingredient: the more you eat, the more you want. The situation for the food industry has been made even better by the glowing endorsements provided by governments urging people to eat more ‘healthy whole grains’.
GRAB MY LOVE HANDLES: THE UNIQUE PROPERTIES OF VISCERAL FAT
Wheat triggers a cycle of insulin-driven satiety and hunger, paralleled by the ups and downs of euphoria and withdrawal, distortions of neurological function, and addictive effects, all leading to fat deposition.
The extremes of blood sugar and insulin are responsible for growth of fat specifically in the visceral organs. Experienced over and over again, visceral fat accumulates, creating a fat liver, two fat kidneys, a fat pancreas, fat large and small intestines, as well as its familiar surface manifestation, a wheat belly. (Even your heart gets fat, but you can’t see this through the semi-rigid ribs.)
So the Michelin tire encircling your or your loved one’s waistline represents the surface manifestation of visceral fat contained within the abdomen and encasing abdominal organs, resulting from months to years of repeated cycles of high blood sugar and high blood insulin, followed by insulin-driven fat deposition. Not fat deposition in the arms, buttocks or thighs, but the saggy ridge encircling the abdomen created by bulging fatty internal organs. (Exactly why disordered glucose-insulin metabolism preferentially causes visceral fat accumulation in the abdomen and not your left shoulder or the top of your head is a question that continues to stump medical science.)
Buttock or thigh fat is precisely that: buttock or thigh fat – no more, no less. You sit on it, you squeeze it into your jeans, you lament the cellulite dimples it creates. It represents excess calories over caloric expenditure. While wheat consumption adds to buttock and thigh fat, the fat in these regions is comparatively quiescent, metabolically speaking.
Visceral fat is different. While it might be useful as ‘love handles’ grasped by your partner, it is also uniquely capable of triggering a universe of inflammatory phenomena. Visceral fat filling and encircling the abdomen of the wheat belly sort is a unique, twenty-four-hour-a-day, seven-day-a-week metabolic factory. And what it produces is inflammatory signals and abnormal cytokines, or cell-to-cell hormone signal molecules, such as leptin, resistin and tumour necrosis factor.4, 5 The more visceral fat present, the greater the quantities of abnormal signals released into the bloodstream.
All body fat is capable of producing another cytokine, adiponectin, a protective molecule that reduces risk for heart disease, diabetes and hypertension. However, as visceral fat increases, its capacity to produce protective adiponectin diminishes (for reasons unclear).6 The combination of lack of adiponectin along with increased leptin, tumour necrosis factor and other inflammatory products underlies abnormal insulin responses, diabetes, hypertension and heart disease.7 The list of other health conditions triggered by visceral fat is growing and now includes dementia, rheumatoid arthritis and colon cancer.8 This is why waist circumference is proving to be a powerful predictor of all these conditions, as well as of mortality.9
Visceral fat not only produces abnormally high levels of inflammatory signals but is also itself inflamed, containing bountiful collections of inflammatory white blood cells (macrophages).10 The endocrine and inflammatory molecules produced by visceral fat empty (via the portal circulation draining blood from the intestinal tract) directly into the liver, which then responds by producing yet another sequence of inflammatory signals and abnormal proteins.
In other words, in the human body, all fat is not equal. Wheat belly fat is a special fat. It is not just a passive repository for excess pizza calories; it is, in effect, an endocrine gland much like your thyroid gland or pancreas, albeit a very large and active endocrine gland. (Ironically, people were correct forty years ago when they labelled an overweight person as having a ‘gland’ problem.) Unlike other endocrine glands, the visceral fat endocrine gland does not play by the rules, but follows a unique handbook that works against the body’s health.
So a wheat belly is not just unsightly, it’s also dreadfully unhealthy.
GETTING HIGH ON INSULIN
Why is wheat so much worse for weight than other foods?
The essential phenomenon that sets the growth of the wheat belly in motion is high blood sugar (glucose). High blood sugar, in turn, provokes high blood insulin. (Insulin is released by the pancreas in response to the blood sugar. The higher the blood sugar, the more insulin must be released to move the sugar into the body’s cells, such as those of the muscle and liver.) When the pancreas’s ability to produce insulin in response to blood sugar rises is exceeded, diabetes develops. But you don’t have to be diabetic to experience high blood sugar and high insulin. Nondiabetics can easily experience the high blood sugars required to cultivate their very own wheat belly, particularly because foods made from wheat so readily convert to sugar.
High blood insulin provokes visceral fat accumulation, the body’s means of storing excess energy. When visceral fat accumulates, the flood of inflammatory signals it produces causes tissues such as muscle and liver to respond less to insulin. This so-called insulin resistance means that the pancreas must produce greater and greater quantities of insulin to metabolise the sugars. Eventually, a vicious circle of increased insulin resistance, increased insulin production, increased deposition of visceral fat, increased insulin resistance, etc., etc., ensues.
Nutritionists established the fact that wheat increases blood sugar more profoundly than table sugar thirty years ago. As we’ve discussed, the glycaemic index, or GI, is the nutritionist’s measure of how much blood sugar levels increase in the 90 to 120 minutes after a food is consumed. By this measure, whole-wheat bread has a GI of 72, while plain table sugar has a GI of 59 (though some labs have observed results as high as 65). In contrast, kidney beans have a GI of 51, grapefruit comes in at 25, while noncarbohydrate