Whether oats should be included in a gluten-free diet has been debated for half a century. In 1995, the largest and most scientifically rigorous study on the safety of oats was published. Investigators concluded that the consumption of oats was safe for adults with celiac disease. Since 1995, several additional studies have been published. Without exception, these investigations found no adverse effects associated with the regular consumption of moderate amounts of oats. However, there are concerns among some authorities on celiac disease that even if oats themselves are safe, they nonetheless may be contaminated with wheat, rye, or barley. Unfortunately, the extent to which contamination of commercial oat products occurs is not known. Ideally, if a patient appears likely to use oats, they should be advised to consume only those products tested and found to be free of contamination.