The U.S. Food and Drug Administration has issued a set of standards for food manufacturers wishing to label a product gluten-free. The limit for foods marketed as gluten-free is 20 parts per million of gluten present. This extends to products labeled free of gluten, without gluten or no gluten. The final rule comes 6 years after the proposed definition of gluten-free was published and 9 years after Congress requested a universal definition. The push for a standard was spurred by an increase of the number of people with celiac disease. FDA Commissioner Margaret Hamburg said adherence to a gluten-free diet is the key to treating celiac disease. She said the new gluten-free definition will help people with this condition make food choices with confidence and allow them to better manage their health.