Going gluten-free because everyone else is?

Food makers often profit handsomely by selling products that are missing something. In this case, what's gone is gluten.

Sales of gluten-free food and beverages are expected to hit $15.6 billion in 2016, a gain of about 48 percent since 2013, as food manufacturers respond to the growing demand from consumers who are convinced that the naturally occurring protein found in wheat and other grain products is to blame for a myriad of health woes.

According to market researcher NPD, about 11 percent of U.S. households now follow a gluten-free diet. Moreover, about one in four consumers believe everyone should quit eating gluten.

However, experts note that many people who are concerned about gluten don't know much about it, a point that was made recently in a bit on "Jimmy Kimmel Live."

"From the perspective of nutrition and health, there is absolutely no reason why somebody who does not have celiac disease or gluten intolerance should spend the extra money on these products, quite the opposite!" wrote Dr. Susan Roberts, a senior scientist at the USDA Human Nutrition Research Center on Aging at Tufts University. "Gluten-free products that are palatable tend to be quite low in fiber, so I worry that they may encourage weight gain."

Of course, lots of people can't tolerate gluten because they do have celiac disease. About 3 million Americans have this condition, in which their immune system damages their small intestine and can make the body unable to absorb nutrients. Celiac disease diagnoses are on the rise, which is likely to fuel even more demand for gluten-free products.

Gluten-free foods are becoming more ubiquitous in specialty markets such as Whole Foods (WFM) and other retailers, including grocery store operators such as Safeway (SWY) and big-box retailers such as Wal-Mart (WMT).

There are a plethora of products to choose from. Kellogg (K), the largest cereal maker, features a lineup of gluten-free products including Rice Krispies. Domino's (DPZ) offers gluten-free pizza but doesn't recommend it to people with gluten sensitivities because it's "prepared in a common kitchen with the risk of gluten exposure." Campbell Soup (CBP) also has a line of gluten-free soups and pasta sauces. There's even gluten-free dog food.

"Careful consideration of pricing compared to alternatives that contain gluten will be of particular importance to the success of most gluten-free products, especially in the current economy," says NPD food and beverage industry analyst Darren Seifer in a press release. "Continued improvement of the taste of gluten-free products will also be important in order to keep consumers purchasing in the gluten-free space."