Potential benefits of a gluten-free diet, from the April 2013 Harvard Health Letter

In the trendy world of popular diets, the latest catchphrase is gluten-free. This eating style is absolutely essential for people with celiac disease, who can't tolerate even small amounts of the protein gluten, which is found in grains such as wheat, rye, and barley. As many as two million Americans may have celiac disease, though only 300,000 or so have been diagnosed with it. Many people without celiac disease are also following a gluten-free diet, reports the April 2013 Harvard Health Letter.

"It's a popular diet of the moment, but it really does seem to provide some improvement in gastrointestinal problems for a segment of the population," says Dr. Daniel Leffler, an international authority on celiac disease and an assistant professor at Harvard Medical School.