John and Jane Doe, residents of 123 Main Street, Anytown, USA, are just your perfectly average American consumers: board-certified gastroenterologists, who will only purchase "Gluten-Free" food items, because they have scientifically confirmed their own celiac sensitivity with extensive medical testing.

That's a joke! Now, from behind a curtain, we bring out the actual John and Jane Doe, the perfectly average American consumers who are experts primarily in NASCAR and sex tips gleaned from Cosmopolitan magazine, and who will only purchase "Gluten-Free" food items because uh, their friend Pam said it really helped her skin look fresher, and they heard a thing on the Today show about how it saved some kid's life somewhere?

A very small percentage of Americans have celiac disease. They should not eat gluten. An estimated (*grain of salt here*) 6% of Americans may have "gluten sensitivity." They might want to avoid gluten, sure. Yet Ad Age notes today that approximately 100% of Americans Who Would Like to Give You Diet Advice are convinced that they must pursue a "gluten-free" diet. Why? "Only 2% of shoppers who buy gluten-free foods do so because they have celiac disease, while 59% said they buy such products because they think they're more healthful, according to a 2013 shopper survey published by the Food Marketing Institute."

Because Americans are doctors, that's why.

Still, [food industry analyst Phil Lempert] predicts that "the bubble will burst" in a couple years. "Gluten-free products are expensive, so that will drive shoppers away from buying them once they realize little or no benefits from the diet." For instance, Betty Crocker gluten-free chocolate- brownie mix costs 38¢ per ounce, compared with 16¢ per ounce for regular fudge-brownie mix.

"As long as you take the gluten out of the brownie mix, a good thing to include in a healthy diet is brownie mix." - John and Jane Doe, American consumerdoctors.

[Ad Age. Photo: ilovememphis/ Flickr]