To the Editor: Drs. Williams, Harris, and Odom presented an excellent overview of common questions regarding celiac disease. ¹ In Table 3, “Fundamentals of the Gluten-Free Diet,” oats are listed as a safe grain. However, commercial oats are often processed alongside gluten-containing grains. Therefore, oats can contain gluten because of cross-contamination. People with celiac disease should eat only oats that are specifically labeled as gluten free. Although most patients with celiac disease can tolerate pure oats, some are intolerant.^2–4

The reason for oat intolerance in some patients with celiac disease is unknown but may be due to the development of an immunologic reaction to avenins, the prolamin storage protein in oats corresponding to gliadins in wheat, secalins in rye, and hordeins in barley.^2–4 The percentage of patients who cannot tolerate oats is also unknown, but it is likely to be low based on one systematic review.⁵ However, in a randomized trial involving 116 children, 10.5% of participants given a diet with gluten-free oats withdrew from the study because of symptoms.⁶ Clinical practice guidelines from the American College of Gastroenterology and Health Canada recommend introducing oats into the diet with caution and monitoring patients closely for adverse reactions.^2,3 Health Canada states that “…oats should only be introduced after all symptoms of celiac disease including weight loss and growth disturbances have resolved and the individual has been on a gluten-free diet for a minimum of six months.”³ These are important facts clinicians must understand when educating patients about a gluten-free diet.

Editor's Note: This letter was sent to the authors of “Celiac Disease: Common Questions and Answers,” who declined to reply.