The last ten years have engendered an explosion of all sorts of low-carbohydrate diets from Atkins to Paleo. Many of these diets not only condemn excess quantities of carbohydrate, but focus on eliminating a particular type of carbohydrate, whether that is high fructose corn syrup, processed starches or high glycemic index carbs. Now a book by cardiologist William Davis, M.D., proposes that a specific type of grain, namely modern wheat, is the mechanism behind many of the world’s chronic diseases. The diet that Dr. Davis espouses is known as the Wheat Belly diet.
Dr. Davis’s central tenant is that genetic manipulations of modern wheat have somehow altered our ability to properly metabolize it. He credits this change with an increase both in overall obesity rates and central obesity. Central obesity, although this theory has recently come under scrutiny, is thought to play a role in the development of type 2 diabetes and cardiac disease. This type of visceral fat is highly metabolic, sending out hormonal signals that play a role in the inflammatory response. Chronic cellular inflammation is a hallmark of type 2 diabetes.
Unfortunately, there isn’t any scientific evidence backing Dr. Davis’s claims. There are no controlled clinical trials comparing a diet high in carbohydrate, but devoid of wheat products, against one high in wheat products. A few years ago, low glycemic index diets were all the rage for both prevention of diabetes and weight loss. But over and over again, the evidence has returned to the single tenet— that in the end, calories matter.
Our understanding of how calories are used by different people has grown tremendously and we know that lowering our calorie intake makes our bodies more efficient in using the calories we supply, making weight loss more difficult. Still, the people who lose weight expend more calories than they take in. The Wheat Belly diet is, in the final analysis, a low-calorie diet and that is why it works.
There are aspects of the Wheat Belly diet that make sense. Reducing the amount of processed foods in your meals and choosing more low glycemic index carbohydrates are excellent ways to cut saturated fat, sodium, and, often, excess calories. The diet’s focus on low-fat protein sources such as chicken and fish, non-starchy vegetables and nuts are healthful choices. Like many of the other lower-carbohydrate diets on the market, reducing the amount of carbohydrate overall tends to cut calories. You can overeat on the Wheat Belly diet, it is just a lot more difficult.
What is enticing about the Wheat Belly diet is that many foods on it can be consumed in unlimited quantities. For example, the following foods have no restrictions: all meats (except processed meats); non-starchy vegetables; real cheeses and olives; flaxseed, coconut and walnut oil. However, fruit and dairy products are limited and, of course, all wheat and oat products banned.
For people with diabetes or even those without, some of the allowed foods, such as regular fat dairy and unlimited red meats, may raise cholesterol levels. And some of the restricted foods, such as fruit and oats, eliminate sources of vitamins, minerals and phytoestrogens.
There are people who are allergic to wheat—this is an entirely different issue. People with wheat allergies do not have celiac disease; rather their bodies produce an antibody to the proteins in wheat. This is a common childhood allergy that can cause bloating, and reducing or eliminating wheat product intake can help. But the Wheat Belly diet is supposed to appeal not solely to those with allergies, but to those interested in losing weight.
Will the Wheat Belly diet harm you? Most likely it will not. Will it help you? If you cut your calories while following the Wheat Belly guidelines, you’ll probably reap the benefits of a lower weight. But is there a scientific rationale tied to the diet’s premise? No.