Wheat Belly, Busted

But as you’ll see, those three factors are dangerous. They build a facade of trust and credibility. They cause us to let down our guard; to cease being the critically-thinking readers that we ought to be. And sometimes, that means we fail to question information that is suspect; we unknowingly accept and perpetuate a myth; we fall victim to false information.

I didn’t set out to write a review of Wheat Belly. I had been heavily researching another unrelated project. Coincidental timing then played a key role. After reading a number of prominent medical studies involving wheat, gluten, weight loss, and celiac disease, I found myself reading Wheat Belly, in which Davis cites some of those exact same studies. 

Except that there was one major problem: Davis’ claims—and his conclusions based on the research studies he cites—were exactly the opposite of what I’d been reading in those very studies. Here are several important examples:

Consider Chapter 3, Wheat Deconstructed, page 36 of the hardcover edition. Davis writes “if we look only at overweight people who are not severely malnourished at the time of diagnosis who remove wheat from their diet, it becomes clear that this enables them to lose a substantial amount of weight.” He supposedly backs up this claim in the very next sentence by continuing, “A Mayo Clinic/University of Iowa study of 215 obese celiac patients showed 27.5 pounds of weight loss in the first six months of a wheat-free diet.” Sounds pretty impressive and compelling … until you realize he’s wrong.

First of all, the study didn’t examine 215 obese patients. Body Mass Index for study participants ranged from underweight to normal to overweight to obese. Secondly, only 25 of those 215 patients lost weight, and the weight loss was not restricted to the obese subset of participants. (Further, 91 of the 215 patients gained weight, but I’ll return to the issue of weight gain among obese celiacs in a moment.) You can read the full text of the study as reported in the original American Journal of Clinical Nutrition article here.

Next consider Chapter 5, The Wheat/Obesity Connection, page 66 of the hardcover edition. Here Davis invokes a study reported in the American Journal of Gastroenterology. He claims that of newly diagnosed celiac disease patients, 39 percent start overweight and 13 percent start obese. Next Davis writes that “by this estimate, more than half the people now diagnosed with celiac disease are therefore overweight or obese.”

Not quite. Actually, the study noted that overweight and obese patients together accounted for 39 percent of diagnoses. The 13 percent obese patients were a subset of the overweight group. By Davis’ questionable math, underweight, normal weight, overweight, and obese celiac disease patients would account for 114% of diagnoses, which is impossible.

At the start of the very next paragraph, he invokes a familiar line nearly identical to that from Chapter 3: “If we focus only on overweight people who are not severely malnourished at the time of diagnosis, celiac sufferers actually lose a substantial quantity of weight when they eliminate wheat gluten.”

I call B.S. You know that study Davis just cited in the previous paragraph of his book to build his case? The same study from which he errantly claimed more than half of newly diagnosed celiacs are overweight? Here is what researchers actually found, and I quote directly: “Of patients compliant with a gluten-free diet, 81 percent had gained weight after 2 years, including 82% of initially overweight patients” (emphasis mine). 

This finding is not buried deep in the report somewhere. It’s important enough that researchers also call it out directly in the top-level abstract. When Davis claims that initially overweight celiac disease patients lose a significant amount of weight on a gluten-free diet, how does he explain the fact that 82% of those patients gained weight … in one of the very studies he uses to back up his questionable claim?

To me this appears to be more than an innocent, but careless, oversight; it is more than a case of blissful ignorance. Those results are front and center in the study, and they directly contradict his claim. It would take an act of willful omission to leave it out; it’s audacious that he cites the study to bolster his claim.

For a third and final example, consider Chapter 4, The Addictive Properties of Wheat, page 50 of the hardcover edition. Here, Davis writes about gluten exorphins, opiate-like compounds created when stomach enzymes take a crack at partially digesting gluten. Researchers are continuing to study how they impact the human body in myriad ways. One branch of such studies uses the drug naloxone, an opiate blocker, to cancel the potential effect of gluten exorphins and other related compounds. 

Davis makes the claim that gluten exorphins are addictive like morphine (another opiate), and that those addictive properties cause you to eat more calories and gain weight. As the theory goes, block the gluten exorphins with naloxone, and you block the addictive properties of wheat-based foods. To back up his boast, he then cites a study, published in the American Journal of Clinical Nutrition, in which binge eaters were left in a room filled with a variety of foods for one hour. Davis writes “participants consumed 28 percent less wheat crackers, bread sticks, and pretzels with the administration of naloxone.” And there you have it! See? Naloxone blocked the evil action of gluten exorphins, and those binge eaters ate fewer calories as a result! Except that’s not what happened.

Here’s the truth: While naloxone appeared to have an impact on the consumption of high fat and high sugar foods, it had no effect that correlated with gluten. In fact, while Davis claims that participants consumed 28 percent fewer wheat crackers, bread sticks, and pretzels, they actually consumed 40 percent more gluten-containing bread sticks.

The three examples I’ve noted are hardly the sum total of the problems I found with the book. There are many others, though I’ve already made my point.

Those of us in the gluten-free community want to agree with Wheat Belly because Davis’ message resonates with us. But it’s an overly simplified message, at times built on tenuous claims. And how would we ever know? He’s an M.D. He’s the expert, right? And he cites all those sexy research studies. 

If I had read this book at another time in my life, I likely would have been none the wiser. I would have read the book, peeked at the citations, and been satisfied. But perhaps serendipity of a certain sort is at work here … that I read this book at precisely that moment in my life when I was best equipped with the knowledge I needed to critically evaluate it. I now pass that evaluation along to you.

For certain, some of what Davis writes is valid. And I have some GF blogging colleagues/friends who know Davis personally. They say he’s a very nice man, which may indeed be true.

But I’m more than disappointed with Davis and Wheat Belly; I’m downright angry. This book can and should be better. We, the gluten-free community, deserve as much. It does an injustice to the very legitimate case against wheat and gluten, and it is insulting to us, the readers. Sadly, Wheat Belly looks polished from a distance, but upon closer inspection it goes belly up. Sections of the book amount to propaganda, fallacies, and unsubstantiated claims. For me, Wheat Belly is a bust.

Are wheat and gluten a health problem? For many of us, undoubtedly. But there’s much more to the story than meets the eye, and you’re not always getting the straight story in Wheat Belly.

–Pete

Image of wheat field courtesy Stock.Xchng / Oeil De Nuit.