There are also some nutritional challenges in a gluten-free diet: people can find themselves deficient in iron, calcium, B-vitamins and vitamin D, Sandquist said. It can be hard to get enough fiber in a gluten-free diet. Also, it's expensive.
Still, for those with celiac disease or gluten sensitivity, avoiding gluten is critical, dieticians said. Gluten is lurking everyone, Slavin said, although the upside of the trend is that it's much easier to find gluten-free products now.
"I had a graduate student with celiac and we had a party for her with no gluten -- and it was not that hard, Slavin said. "We had salad, meats, cheeses, fruits -- it's expensive, and it's a little harder than straight grains, but it wasn't too limited."
Only 1 percent of the population has celiac disease, and 6 percent are gluten-sensitive, although it might seem like more, with celebrities like Miley Cyrus and Gwyneth Paltrow talking about it. And many people are self-diagnosing themselves with gluten sensitivity, Sandquist said.