A gluten-free diet is for people with celiac disease, not those without it. Numerous studies show that a gluten-free diet can help those with celiac disease feel better and have fewer symptoms by reducing the effects of their disease. Researchers also know that it isn’t clear whether or how often gluten causes problems in people who don't have celiac disease but think they are sensitive to the protein because symptoms improve when they go on a gluten-free diet.