Of these, 28% could still eat egg without reacting and were considered allergy-free.

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The treatment of a serious gluten allergy is a gluten-free diet, which has a lot of meat, fruit, milk and potatoes.

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The Food Allergen Labeling and Consumer Protection Act of 2004, which legislated the requirement for food allergy labeling guidelines, also required the FDA to implement rules for voluntary gluten-free labeling guidelines by August 2008.

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Levitsky said a gluten-free diet might have benefits for those with mild allergies, or even no allergy at all.

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