Transcript for Doctor Who Started Gluten-Free Fad Says He Got It Wrong
index," a new study sending shock waves to those on a gluten-free diet. In a stunning reversal, whose findings kicked off the gluten-free craze, says now he got it wrong. Abbie Boudreau has the story. Reporter: Gluten-free diets, popular with many celebrities, who say the gluten-free diet helped them lose weight. Even jimmy Kimmel couldn't hold back. What is gluten? What is this thing you will not eat? It is a part, I believe, of the wheat that -- I really don't know. Reporter: But the same doctor whose research is credited with sparking the gluten-free debate in 2011, is now reversing his opinions. We've just conducted a new study. We found that people who believed that gluten was causing them gut symptoms, we could find no evidence for it. Reporter: He says hard-to-digest sugars in wheat, rye and barrelly are likely to be the real culprits, not gluten. For those with sill yak disease, gluten-free is a must. But those who feel that go gluten-free would rid them of stomachaches and weight gain. He insists this time, he is positive the problem is seldomly due to gluten. For "Good morning America," Abbie Boudreau, ABC news, los Angeles. Wow. Joining us now, ABC chief health and medical editor, Dr. Richard Besser. The gluten-free diets have been popular in recent years. Very popular. I think part of the reason is celebrities talking about it for weight loss. Celiac disease is a real thing. These are the same doctors that did the study that says you may not have celiac disease but have a problem with gluten. If you don't have celiac disease but you believe you're feeling better because of the gluten-free diet, what do you say to those folks? There's a major mind/body connection. The whole people were off gluten. One-third they put on high gluten, low gluten and no gluten, all of them said their symptoms got worse. The belief this is working for you may actually help with your symptoms. And that's real. That's what I want to ask you is. Is there any harm just getting rid of gluten? I mean, gluten is in wheat, in barley and rye. It's everywhere. It's a major life change to get it out of your diet. The one thing I worry about, could you have a problem that is caused by something medically that you're ignoring. I would get checked out first to see what's going on. And then, realize that this is -- there's a gluten fad out there. Some people have a real problem. But not everybody.
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