It's wonderful to make an informed choice but to so so without having a clue just goes to show you how gullible we are to food fads. I highly doubt those people are gluten free to be honest. Nobody makes such a drastic dietary change without knowing at least something.
"No matter how developed you are in any other area of your life, no matter what you say you believe, no matter how sophisticated or enlightened you think you are, how you eat tells all." - Geneen Roth