Gluten is a sticky protein in wheat, barley, rye, AND oats, naturally. But the gluten in oats is called avenin; the gluten in wheat, barley and rye is called gliadin. Shorthand, we use the broader term "gluten" in the place of the more specific term "gliadin". That's why we can call oats "gluten-free". And it is true that many people with a gliadin problem, are able to digest avenin. Some, however, are not. And no effort to label oats as "gluten-free" will make it so - it always will contain its specific gluten called avenin. For the people who think "gluten-free" is a health fad: It is not. Celiac disease is a severe autoimmune disease, with many consequences if neglected. Roughly 1 in 100 of people worldwide have gluten sensitivity. It's real (because it's in your genes), and it can't be wished away. [This article first appeared as a letter in the New York Times health blog 4/14/2018]