(CNN) – The Food and Drug Administration set new rules Friday for food products labeled gluten-free.
Health officials say it will help millions of Americans who have celiac disease.
Gluten is a protein composite found in wheat, rye and barley.
When people with celiac eat gluten, it triggers the production of antibodies that damage the lining of the small intestine.
Under the new rules, foods labeled gluten-free must contain fewer than 20 parts per million of gluten.
The gluten-free food industry has exploded over the past few years.
More than $4 billion of gluten-free products were sold in 2012, according to the market research company Packaged Facts.
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