Samantha Nelson

USA TODAY

As gluten-free diets become popular, many critics of the trend say gluten and wheat allergies or sensitivity are imagined.

But a recently released study found that the uncomfortable symptoms some people experience after eating wheat and related products aren’t in their heads, but in their intestines.

The study's findings suggest that those who experience symptoms such as abdominal pain, bloating and fatigue after eating wheat and related products have a weakened intestinal barrier.

The study was led by researchers from the Columbia University Medical Center (CUMC) is published in the journal Gut.

“Our study shows that the symptoms reported by individuals with this condition are not imagined, as some people have suggested,” said co-author Dr. Peter H. Green, a professor of medicine at CUMC and director of the Celiac Disease Center, in a press release from CUMC. “It demonstrates that there is a biological basis for these symptoms in a significant number of these patients.”

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The study’s researchers examined 80 people with non-celiac gluten or wheat sensitivity (NCWS), and 40 people with celiac disease.

Celiac disease is an autoimmune disorder that damages the small intestine of an individual—who is susceptible to the disease—upon eating gluten. Those with NCWS experience symptoms similar to celiac disease but lack the blood, tissue and genetic markers that come with the autoimmune disorder.

An explanation for NCWS offers that exposure to wheat, rye or barley grains sets off a severe systemic immune response instead of a localized immune response in the intestine, according to the CUMC press release.

The researchers discovered that although the NCWS group did not have cytotoxic T cells found in those with celiac disease, they had markers of intestinal cellular damage related to a severe systemic immune activation.

The study stated that NCWS patients who were excluded wheat and related products from their diets for six months saw improvement in their symptoms and effects.

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According to the CUMC, without any biological markers to indicate someone has NCWS, it was estimated that about 3 million Americans are affected by it, which is the about the same amount of people affected by celiac disease.

“The data suggest that, in the future, we may be able to use a combination of biomarkers to identify patients with non-celiac wheat sensitivity, and to monitor their response to treatment,” said Dr. Armin Alaedini, assistant professor of medicine at Columbia and the study’s leader.

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