As Canadians gather this weekend to celebrate Thanksgiving, there is a growing movement afoot to demonize one of the staples of the Canadian harvest: wheat.

An increasing number of books, blogs and celebrities have fingered wheat as the cause of a variety of conditions, from obesity to heart disease, as well as a host of digestive problems.

One of the most talked-about health books right now is Wheat Belly: Lose the Wheat, Lose the Weight and Find Your Path Back to Health, a New York Times bestseller by U.S. cardiologist Dr. William Davis.

'I think people are willing to do anything to alleviate their digestive concerns and try anything to resolve their weight issues.'— Susan Watson, registered dietitian

Earlier this year, reality-TV star Kim Kardashian made headlines when she announced that she had cut wheat from her diet.

"I think people are willing to do anything to alleviate their digestive concerns and try anything to resolve their weight issues," says Susan Watson, a registered dietitian in Winnipeg, about the growing anti-wheat movement.

"From a general health standpoint, unless you're celiac or have a diagnosed wheat intolerance, cutting any food group or any food product completely out of your diet is not generally recommended," says Watson.

The antipathy to wheat is partly attributable to a growing awareness of celiac disease, an autoimmune condition that affects approximately one in every 133 people in Canada. Celiac disease occurs when the small intestine is unable to properly digest gluten, a protein that appears in wheat as well as other grains such as barley, rye and spelt.

For celiacs, eating gluten-rich foods can make it difficult for the body to absorb nutrients, which can lead to everything from anemia to osteoporosis.

There is also another subset of people who suffer "non-celiac gluten sensitivity," which can include an allergy to wheat.

Although celiacs and the wheat allergic may experience similar symptoms, such as cramps and diarrhea, "a wheat allergy does not damage the intestine, whereas celiac disease does," explains Novella Lui, a Toronto-based dietitian.

Going gluten-free

In any event, doctors and naturopaths generally counsel celiacs and those with non-celiac gluten sensitivity to go gluten-free.

As a result, gluten-free guides have sprung up all over the place, including such high-profile titles as The G-Free Diet by Elisabeth Hasselbeck, co-host of the popular U.S. daytime talk show The View and a celiac herself.

But the current anti-wheat trend isn't simply a response to celiac disease. In fact, it is increasingly being pitched as a healthy choice for everyone, which is what Davis argues in Wheat Belly.

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Gluten-free products, like this baguette, has come a long way in approximating the taste and consistency of traditional wheat-based baking. (Larry Crowe/AP)

Raises blood sugar

Davis says he discovered the harmful effects of wheat several years ago, "when I made myself diabetic by accident."

Despite being on a low-fat, vegetarian diet and jogging up to eight kilometres a day, Davis found that his blood sugar was inexplicably spiking.

It didn't become clear to him what was going on until he began doing research into how to prevent heart disease. Then he learned that it was impossible to control the risks of heart disease – such as coronary atherosclerosis – if the patient was diabetic or pre-diabetic.

And one of the things that raises blood sugar is wheat, which is the basis of everything from bread to pasta to pastries.

"The glycemic index of wheat is very high, and wheat products dominate the diets of most Canadians and Americans," Davis said during a phone interview from his office in Milwaukee, Wis.

Not only does wheat raise blood sugar, but Davis says that in the digestion process, one of the proteins contained in wheat — gliadin — becomes "degraded to a morphine-like compound" that creates an appetite for even more wheat.

A little harsh?

Davis contends that significant wheat consumption leads to the development of "deep visceral fat" in the stomach area, and that cutting it out of a person's diet can yield significant weight loss.

But Susan Watson, who runs the nutrition counseling firm A Little Nutrition, says that while the general message of Davis's book is good, the prescription is a little harsh.

"If you avoided white bread and white rice, and switched it with whole-grain bread and whole-grain rice, you're getting a way better health benefit than cutting out [all] wheat."

Two of the higher-profile proponents of a gluten-free diet are Kim Kardashian and pop singer Miley Cyrus. In May, Kardashian posted a flattering picture of herself in black lingerie online as proof of the wonders of a GF diet. However, celebrity-watchers pointed out that the picture was actually two years old, before she'd gone on the diet.

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Reality-TV star Kim Kardashian has emerged as one of the most visible proponents of a gluten-free diet. (Matt Sayles/AP)

Watson says that any celebrity touting a particular diet might well be getting some sort of financial kickback. Furthermore, she says it's confusing to consumers.

"So what if so-and-so has found all these health benefits – their health concerns are not necessarily the same as the individual that's reading it or seeing it on TV," Watson says.

Market share

Even so, it's clear that gluten-free products are commanding an ever-increasing market share.

A July 2011 report by Agriculture and Agri-Food Canada said that the gluten-free market in the U.S. reached about $1.3 billion US in sales in 2011, and was expected to achieve a growth rate of 31 per cent from 2011 to 2014.

"The market has been growing significantly year over year, so I don't see it as a fad like the grapefruit diet or that sort of thing," says Sue Newell, communication and education officer at the Canadian Celiac Association.

Newell says that if you add celiacs and those with a gluten sensitivity, you're looking at six per cent of the population.

"Six per cent of the population is a non-trivial amount, and these people are not going to go back to eating wheat," she says.

Furthermore, she says that among general consumers, the term gluten-free has come to have positive connotations.

"It's perceived as better-quality food, and it's perceived as healthier and better for your family," Newell says, likening it to kosher food, which enjoys a similarly positive brand identification.

Nutritionists agree, however, that gluten-free eating is not inherently healthier. Many of the ingredients that are substituted for wheat – such as rice flour or potato starch – are just as rich in carbohydrates.

Davis, too, is wary of people quitting wheat only to embrace gluten-free foods, "which send your blood sugar and insulin sky-high, even more so than wheat."

While he bemoans the Western appetite for wheat, Davis doesn't plan to make it a political cause. He says the wheat industry, with its accompanying lobby, is too strong to take on.

"These people have incredible power, clout and finances. It's probably a pointless battle to even try to fight," he says.

"It's all about education, not trying to legislate this."