Gluten-free food fad fueled by celebrity factor

Gwyneth Paltrow gushes over gluten-free. Chelsea Clinton's wedding cake was baked without it. The new Old Spice guy avoids the ubiquitous protein to help stay buff. Odds are good you have tried — or at least encountered — a product with the gluten removed.

That's because gluten-free is what low-carb was a decade ago: The "it" diet discussed on daytime talk shows, promoted by actresses and adopted by masses. Grocery aisles are stocked with the likes of gluten-free pasta, crackers, cereal and beer.

Americans are enthusiastically exiling a dietary staple that wasn't even in most people's vocabulary a decade ago.

But why?

Gluten is not bad to eat. Only a small percentage of people can't tolerate the protein, which occurs naturally in wheat, barley and rye. Plus, banning gluten from your diet can be hard.

It is an essential element of traditional breads and pastas (it gives them their structure). It is used as a thickening agent in processed foods, such as ketchup and ice cream. And cutting out gluten is no guarantee of weight loss.

The fad seems to be partly fueled by the celebrity factor: Paltrow talks it up on her website, Clinton stirred online chatter this summer when she ordered a gluten-free cake for her big day, and the muscular guy on the funny Old Spice commercials told Jay Leno gluten is one of the things he cut from his diet.

Then there are the claims that going "G-free" makes you feel more energetic.

"I feel better when I don't do it. If I go out to a restaurant with friends and I have a beer and a plate of pasta I'm going to feel it the next day. No one wants a gluten hangover," said Silvana Nardone, former editor-in-chief of Every Day with Rachael Ray magazine.

These claims are common, if hard to prove. But that hasn't slowed the industry's growth.

U.S. sales of gluten-free food have more than doubled since 2005 to more than $1.5 billion, according to the market-research company Packaged Facts.

Gluten does affect some people, notably people with celiac disease. But celiacs, who get an immune reaction if they eat food with gluten, such as bread or pasta, represent less than 1 percent of the population.

Some other people have less-severe gluten allergies or sensitivities. Dr. Alessio Fasano, director of the Center for Celiac Research at the University of Maryland School of Medicine, figures that up to 8 percent of the U.S. population has a sensitivity to gluten.

Yet about one-quarter of U.S. adults are either trying to reduce or completely avoid gluten, according to the marketing firm NPD Group's Dieting Monitor.

"Some of the people we're talking about most are people who are dabbling in raw foods and dabbling in vegan and dabbling in different things, and they see gluten-free as part of that world," said Shauna James Ahern, better known as the popular Seattle blogger "Gluten-Free Girl."

Why people report feeling better on a gluten-free diet is not clear. People who eliminate gluten-rich foods may eat more produce, and therefore have a more healthful diet overall, said Dee Sandquist, a spokeswoman for the American Dietetic Association.

Fasano suggests that gluten is harder to digest, perhaps because it was only introduced to the human diet about 10,000 years ago. In evolutionary terms, that's not a lot of time to adapt to digesting a new protein.

Dr. Brian Bosworth, associate director of the Gastroenterology Fellowship Program at New York Presbyterian Hospital/Weill Cornell Medical Center, noted that while gluten can be an irritant to some people, he wouldn't say it's harder to digest for everyone.

"I don't think that, in general, that there's a reason to strictly avoid it," said Bosworth, who has celiac disease.