Many probiotics "contaminated" with gluten

A study conducted by the researchers at the Celiac Disease Center at Columbia University Medical Center (CUMC), US has revealed that 55% of 22 “top-selling” probiotics contain gluten.

Probiotic are commonly taken by patients suffering from celiac disease for their “theoretical effect” in promoting gut health, CUMC said.

“Still, these findings raise troubling questions

Co-author Benjamin Lebwohl

“We have previously reported that celiac patients who use dietary supplements [such as probiotics] have more symptoms than non-users, so we decided to test the probiotics for gluten contamination, said Samantha Nazareth, a gastroenterologist at CUMC and the first author of the study.

Gluten, a protein found in wheat, rye and barley products, can cause people with celiac disease pain and in some cases can increase the risk of cancer.

In the CUMC study, the researchers used liquid chromatography-mass spectrometry to quantify gluten content.

Of the probiotics that tested ’positive’ for gluten, however, most contained less than 20 parts per million of the protein, and would be considered gluten-free by Food and Drug Administration (FDA) standards. But, four of the brands contained in excess of that amount.

“We have been following reports in the scientific literature and news media on inaccurate labelling of nutritional supplements, and it appears that labels claiming a product is gluten-free are not to be trusted, at least when it comes to probiotics,” said Peter Green, professor of medicine and director of the Celiac Disease Center.

“This is a potential hazard for our patients, and we are concerned.”

However, researchers at the Celiac Disease Center, US are unsure whether trace amounts of gluten could cause symptoms or otherwise harm patients with celiac disease.

“We know that most patients with celiac disease only develop intestinal damage when consuming more than 10 milligrams of gluten daily, and it is unlikely that contaminated probiotics can lead to that amount unless patients are ingesting mega-doses,” said Benjamin Lebwohl, assistant professor of medicine and epidemiology at the Celiac Disease Center and a co-author of the study.

“Still, these findings raise troubling questions,” Lebwohl said.

“Why is there any gluten in these products? Why should the consumer pay any attention to gluten-free labeling on such products? And given the great consumer interest in probiotics, will regulatory bodies take action to protect the public?”