ATLANTA (AP) - It sounds like an unfolding epidemic: A decade ago, virtually no one in the United States seemed to have a problem eating gluten in bread and other foods. Now, millions do.

Gluten-free products are flying off grocery shelves, and restaurants are boasting of meals with no gluten. Celebrities on TV talk shows chat about the digestive discomfort they blame on the wheat protein they now shun. Some churches even offer gluten-free Holy Communion wafers.

"I don't know whether there's more people getting this or that more people are noticing" they have a problem, said the Rev. Richard Allen, pastor at Mamaroneck United Methodist Church, north of New York City.

Or is it just another food fad?

Faddishness is a big part of it. Americans will spend an estimated $7 billion this year on foods labeled gluten-free, according to the market research firm Mintel. But the best estimates are that more than half the consumers buying these products - perhaps way more than half - don't have any clear-cut reaction to gluten.