Celiac.com 01/08/2008 - Our recent article on oats brought a number of comments calling our attention to another recent study in which certain types of oats were found to be more beneficial, while others were more likely to be problematical. There still isn’t any official definitive evidence one-way or the other as to just how safe oats are for folks on a gluten-free diet, though there are more studies of this nature being undertaken, and data collection and genetic mapping and testing help us to build a better picture.
A team of Italian and Australian doctors conduced in vitro tests on three different kinds of oats. They wanted to see if certain kinds of oats showed any kind of toxicity in people with celiac disease. These tests showed that the Avenins of the Italian variety Astra and the Australian variety Mortlook showed a much higher activity than those of the Australian Lampton variety, while Rice of the Roma variety showed no activity. Gliadin which is found in wheat and rye showed the expectedly high levels of activity.
Of the oat types tested in this study, the Lampton variety seems to be safer than either the Astra or the Mortlock. However, even oats that are “safer” must still be processed in a dedicated facility that is free of contamination and routinely tested to make sure they meet the minimum levels to be gluten-free. For oat products to be considered gluten-free, they must show less than 20ppm of gliadin.
A study published in the New England Journal of Medicine by Trisha Thompson, M.S., R.D.,* showed that no commercial brand of oats were reliably gluten-free. In fact, nine of the twelve samples from three major brands of oats showed gluten levels ranging from 1,807 to 23 ppm.
There are several companies who now sell "certified gluten-free oats," which are oats that are farmed, harvested, processed and packed using special methods to avoid cross-contamination with gluten during every step of the way. Gluten-free oats currently sell for around $4 to $5 a pound. These type of oats are typically tested for gliadin to less than 3ppm, and are thus considered safe for celiacs who are not sensitive to Avenins.
As far as certain types of oats being better than others, it’s worth some checking, but I’m unsure of the availability of, say, the Lampton strain in America. Also, given the results of commercially available oat brands, the question of the conditions under which the oats were processed becomes very important. Previous studies have shown children with celiac produce significantly greater numbers on antibodies to oat protein than non-celiac children (Scand J Gastroenterol. 2003 Jul; 38(7):742-6).
Many folks with celiac disease are looking to avoid contamination, as no one wants to suffer the unpleasant symptoms of a gluten reaction. Basically, people just want to know what’s safe and to be able to enjoy those items without worrying about getting sick. Since cross-contamination is such a problem of particular importance to celiacs, and since oats grown and processed commercially are likely not gluten-free, it would seem wise to start with gluten-free oats just to be on the safe side.
But anyone looking for a definitive answer will just have to wait. And remember, as with so much with the gluten-free diet, you are the best judge of your own body.
*Thompson T. Gluten Contamination of Commercial Oat Products in the United States. N Engl J Med 2004; 351:2021-2022
Journal of Gastroenterology and Hepatology 22 (4), 528–531, 2007.
Marco Silano, Mariarita Dessì, Massimo De Vincenzi, Hugh Cornell (2007).