One of the sub-chapter headings of chapter five of Wheat Belly is “WHOLE GRAINS, HALF TRUTHS.” You could have titled the chapter, “UNTRUTHS ABOUT WHOLE GRAINS” and that would have been much more accurate. The book abandons all pretense of actually responding to the scientific literature and just makes up stories. Once again, it leads with the unsurprising fact that Americans are fat, which is not a news flash. But the book is responsible to explain, using the available scientific data, that it is specifically the whole grains in our diet that are making us obese and creating the belly fat that the book is so worked up over. It doesn’t even try to make that case and has to ignore mountains of scientific evidence that completely contradict what the book claims.
The book makes a misleading but plausible-sounding case for why wheat is bad for you. It claims that wheat raises insulin levels because of its high glycemic index, thus creating belly fat (visceral adiposity). But the book does not refer to a single scientific study that shows that whole grain consumption causes this belly fat The idea that belly fat is uniquely bad for you is completely correct, the vast bulk of the scientific evidence shows that the more belly fat you have, the worse your overall health statistics are. And nobody disputes this claim. Yet the book claims the following:
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.
What does the scientific evidence actually say? The actual scientific studies are unanimous the opposite direction. Whole grain consumption drops insulin levels, reduces the amount of belly fat and creates lower levels of obesity in people who eat it regularly. The Multi-Ethnic Study of Atherosclerosis (MESA) showed the following:
Concordant with previous research, whole grain intake was inversely associated with (meaning the more whole grain you ate the less you had of) obesity, insulin resistance, inflammation and elevated fasting glucose or newly diagnosed diabetes.
In 2003, a study called the Insulin Resistance Atherosclerosis Study was done at the University of South Carolina; Dr. Liese published the results in The American Journal of Clinical Nutrition, stating in the conclusion: “Higher intakes of whole grains were associated with increases in insulin sensitivity.” This means there was less insulin circulating and a lower risk of diabetes.
The Journal of Nutrition published a study in 2009 titled, “Whole-Grain Intake and Cereal Fiber Are Associated with Lower Abdominal Adiposity in Older Adults.” People who ate more grain had less belly fat than those who ate less whole grain. A 2003 study published by Dr. Liu from Harvard in The American Journal of Clinical Nutrition stated:
Weight gain was inversely associated with the intake of high-fiber, whole-grain foods but positively related to the intake of refined-grain foods, which indicated the importance of distinguishing whole-grain products from refined-grain products to aid in weight control.
People who ate whole grains weighed less.
In the interest of space, I have limited my references to a few of the many, many studies that show the same thing. Yet the book tries to tell you the opposite, stating:
According to accepted dietary wisdom, if something that is bad for you (white flour) is replaced with something that is less bad (whole wheat), then lots of that less-bad thing must be great for you. By that logic, if high-tar cigarettes are bad for you and low-tar cigarettes are less bad, then lots of low-tar cigarettes should be good for you.
This analogy gets it backwards. If you replace something that causes a problem (white flour and refined, processed foods cause belly fat) with something that prevents it (whole grain reduces belly fat) then that is like replacing high-tar cigarettes with fresh mountain air. If you are attempting to reduce your insulin level and you remove the whole grains from your diet for foods higher in animal protein and fat, you are replacing mountain air with high-tar cigarettes.
What are the effects of high-fat, high-protein foods on belly fat and insulin resistance? PNAS published a study in 2008 by Dr. Hancock at Washington University titled, “High-fat diets cause insulin resistance despite an increase in muscle mitochondria.” A significant marker for the amount of belly fat in the body is CETP mRNA (this is the RNA that makes an enzyme that helps fat cells store cholesterol). High fat diets reliably increase the circulating level of this marker. A major review article published in Nutrition Research Reviews by Dr. Despres at the University of Laval states,
Thus, it appears that fat oxidation does not acutely adjust to match a high fat intake, until body fat deposition leads to fat cell hypertrophy and increased lipolysis, which by itself stimulates fat oxidation, resulting from the increased flux of free fatty acids originating from the adipose depot (Schutz et al. 1992, who have shown that a substantial gain in body fat may be needed before a new fat balance is reached under conditions of chronic exposure to high fat intake). Thus, obesity may be ‘the price to pay’ for an individual to achieve fat balance with a high fat intake. If this accumulation of fat occurs in the peripheral (gluteal-femoral) depots, adverse metabolic effects are likely to be minimal, whereas those who preferentially accumulate triacylglycerols in the abdominal visceral depot will be more likely to develop insulin resistance and dyslipidaemias.
In plain English this means that when you eat a lot of fat, your body doesn’t start burning it effectively and the fat accumulates, creating a fat belly. It’s not whole grains like wheat that do this. This is the exact opposite of what Wheat Belly claims.
Wheat Belly doesn’t try to address the scientific evidence because that mountain is too tall for it to climb. Instead, the book hopes you won’t investigate the facts yourself and tries to lead you to cut back on whole grains to reduce your insulin resistance and belly fat. This advice is just as good as advising someone to smoke two packs of Marlboros a day to avoid lung cancer.
But this chapter gets even worse. In the section where it talks about celiac disease and obesity, it completely misleads the reader about what is contained in a study that the book lists the reference for. The study is titled, “Overweight in celiac disease: prevalence, clinical characteristics, and effect of a gluten-free diet.” Here’s what the book says about it,
One such recent ten-year tabulation of newly diagnosed celiac patients showed that 39 percent started overweight (BMI 25 to 29.9) and 13 percent started obese (BMI ≥ 30). By this estimate, more than half the people now diagnosed with celiac disease are therefore overweight or obese.
However the book has it exactly wrong. The article states that 39% were overweight, including 13% that were obese. Only 39% of the patients were overweight or obese, less than half! Any reading of the study simply can’t support the claim of the book. But again, celiac disease is a non-issue. There is no disagreement that patients with celiac disease get healthier if they adopt a gluten free diet. The book wants you to read about celiac disease as if you have it, and unless you are in the small subset of the population that has it, studies about patients with it don’t apply to you.
To close out the chapter, the book tries to plead again that wheat and wheat alone is the cause of all obesity, without ever giving any evidence to back that claim up and ignoring the large body of evidence that states just the opposite. The book says,
It makes perfect sense: If you eliminate foods that trigger exaggerated blood sugar and insulin responses, you eliminate the cycle of hunger and momentary satiety, you eliminate the dietary source of addictive exorphins, you are more satisfied with less. Excess weight dissolves and you revert back to your physiologically appropriate weight. You lose the peculiar and unsightly ring around your abdomen: Kiss your wheat belly good-bye.
Yet this all falls apart if blood sugar and insulin responses aren’t made worse by wheat. If whole grains do what we show they do, reduce insulin resistance and decrease visceral fat then this chapter’s primary argument falls to the ground. To quote The Low-Carb Myth by Whitten and Smith:
… insulin is not the major factor that determines how fat or lean we are. There is no body of peer-reviewed scientific studies that supports the idea that insulin causes people to be fat. Rather, the evidence is conclusive that insulin levels do not determine fatness.
A review article published in May, 2006 Obesity Review by Dr. Diaz at the Institute of Nutrition and Food Technology in Chile discussed the hypothesis that high glycemic index foods cause high insulin levels and therefore cause obesity. It stated the following in its abstract:
The purpose of this review was to examine the role of glycaemic index in fuel partitioning and body composition with emphasis on fat oxidation/storage in humans. This relationship is based on the hypothesis postulating that a higher serum glucose and insulin response induced by high-glycaemic carbohydrates promotes lower fat oxidation and higher fat storage in comparison with low-glycaemic carbohydrates. Thus, high-glycaemic index meals could contribute to the maintenance of excess weight in obese individuals and/or predispose obesity-prone subjects to weight gain. Several studies comparing the effects of meals with contrasting glycaemic carbohydrates for hours, days or weeks have failed to demonstrate any differential effect on fuel partitioning when either substrate oxidation or body composition measurements were performed. Apparently, the glycaemic index-induced serum insulin differences are not sufficient in magnitude and/or duration to modify fuel oxidation.
Again, in plain English, we have looked for scientific evidence that high glycemic index foods cause obesity. There isn’t any.
The problem is that this is the core argument of Wheat Belly. The misguided idea is that high glycemic index foods of all types will cause this insulin to spike, causing obesity and belly fat. This is wrong, as I’ve just shown, but if you didn’t read the book carefully, you might just come away thinking that it’s only recommending removing wheat. It’s really advocating a low-carbohydrate diet. The book wants you to avoid all types of carbohydrates. To make this abundantly clear, at the end of the chapter the author shows that it isn’t really wheat or gluten he’s concerned about, but all carbohydrates, warning readers away from spelt, kamut, potatoes, rice and corn.
This isn’t a healthy way to eat. This book is making dietary advice that is most harmful to the people who are paying the most attention to the book’s message.