It's so difficult to get a straight answer to this question - but Nutrition Diva clears up the confusion.
Q. There's some controversy about whether wheat grass or barley grass actually contains gluten. Is it safe for people with Celiac disease?
A. You’re not kidding. Getting a straight answer on this question is not easy! Some insist that as long as the plant has not started to go to seed, the grass will be gluten free. If you’re growing and harvesting your own, that would be fairly easy to determine. But with a processed product containing wheat grass juice or powder, there’d be no way of knowing. Products which have been tested and certified as gluten-free should be safe. But why risk it, especially when you can get the same nutrients in other foods? Despite the rather extravagant claims, there’s nothing that special about wheat grass, nutritionally speaking. I suggest having a salad instead.
Fresh wheat grass from Shutterstock