Celiac disease sufferers cannot tolerate gluten, a protein found in wheat, barley and rye, and must follow a gluten-free diet. Therefore, they must rely on alternative grains such as rice and millet for their gluten-free baked goods.
But a study published June 1 in the Journal of the American Dietetic Association found significant concentrations of gluten in supposedly pure samples of alternative grains. In some cases, the concentrations were far above levels that would cause recurrent celiac disease symptoms in those with the condition.
FDA Standards Would Consider Single-Ingredient Alternative Grains "Gluten-free"
The U.S. Food and Drug Administration has proposed gluten free labeling standards calling for "gluten-free food" to contain no more than 20 parts per million of gluten. Under these proposed regulations, the FDA would assume that many single-ingredient foods, including gluten free grains and flours made from those grains, also are gluten-free.
However, many celiac disease patients say they react to less than 20 parts per million of gluten contamination, and many have given up grains entirely because they react to all grain products. Some in the gluten intolerant community believe their reactions stem from an inability to digest any grains, gluten-containing or not, while others believe the problem is gluten contamination in those alternative grains.
Oats, for example, are not considered "inherently gluten-free" because research suggests that commercially available oats may be contaminated with wheat, barley and rye in the fields or during harvesting and processing.
But some celiac disease sufferers have questioned why all other grains, including those deemed "inherently gluten-free," would not also be contaminated, since farmers generally use the same fields, harvesting and storage equipment for all grains, regardless of whether they contain gluten.
Researchers Used Sensitive Gluten Test to Detect Contamination
In the Journal of the American Dietetic Association report, "Gluten Contamination of Grains, Seeds, and Flours in the United States: A Pilot Study," researchers looked at 22 "inherently" gluten-free grains, seeds and flours that were not specifically labeled "gluten-free," but that would meet the proposed FDA requirements for single-ingredient foods to be considered gluten-free.
The research team, led by celiac disease nutritionist Tricia Thompson in Manchester, Mass., sent the unopened samples to a company specializing in gluten analysis, which tested them each twice for gluten using a testing method that is accurate down to 5 parts per million.
The study found that nine of the 22 samples tested contained enough gluten to register on the test, with mean gluten levels ranging from 8.5 parts per million to 2,925 parts per million.
Seven of the samples, or about one-third, contained mean gluten levels above 20 parts per million, meaning they would not qualify for a "gluten free food" label under the proposed FDA regulations.
The worst offenders included soy flour, which had 2,925 parts per million of gluten, sorghum flour, which was contaminated with 234 parts per million of gluten, and two different brands of millet flour, which contained up to 327 parts per million of gluten. Millet whole grain, buckwheat flour and white rice flour also contained detectable levels of gluten.
The study, which was funded in part by gluten free foods manufacturer Schar USA, did not specify what brands of grains and flours were tested.
Study: Contamination Poses Health Risk to Celiac Disease Patients
The study results indicate a potential health risk for those with celiac disease, the authors said.
"The findings of the current study indicate that some inherently gluten-free grains, seeds, and flours not labeled gluten-free are contaminated with gluten," they wrote. "The consumption of these products can lead to inadvertent gluten intake."
The authors recommended a much larger study to determine whether certain grains and seeds are more likely than others to be contaminated, and suggested that the FDA might consider modifying its proposed rule on gluten free labeling for single-ingredient foods.
Jane Anderson - Jane M. Anderson spends as much time as possible on the water, working and sailing on boats. She grew up sailing Sunfish and Rhodes 19s on ...
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