By Molly Daly

PHILADELPHIA (CBS) — A locally-based advocacy group says an important message is being drowned out amid the gluten-free craze — that people with Celiac disease must be properly diagnosed before they make changes to their diets.

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Celiac is a disease in which the immune system’s overreaction to gluten damages the delicate intestinal lining, where nutrients are absorbed.

National Foundation for Celiac Awareness Founder and Philadelphian Alice Bast says a lot of people are eliminating gluten from their diets, thinking it’s healthier in general, when there’s no science to back that up.

“Which really overshadows the fact that there’s one percent of Americans that have to be on a gluten free diet, and it’s their treatment,” she says, “just like insulin is a treatment for diabetes, gluten-free diet is a treatment for celiac disease.”

And Bast says you should not go off gluten before a doctor performs the only definitive tests for celiac.

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“That includes a blood test,” she says, “and then they get a biopsy, and then, if they test positive, they go gluten free. It’s really important to get tested.”

Celiac is different from gluten sensitivity, for which there is not yet a test. If you or a close relative test positive for celiac, Bast says it’s important for everyone to get tested, since it can run in families.

“And they may have no symptoms at all,” Bast warns.

Click here for more information, including a symptoms checklist:

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