What is the diet?

Following a gluten-free diet involves avoiding wheat, barley, rye and all foods made with these ingredients. Reading ingredient labels for consumed foods, beverages, medications and supplements is essential to avoiding gluten.

What conditions is the gluten-free diet used for?

Why is the gluten-free diet being recommended?

A strict, life-long gluten-free diet is the only treatment available for celiac disease and non-celiac wheat sensitivity (NCGS).

Celiac disease is an autoimmune disease triggered by gluten ingestion, which damages the small intestine and interferes with absorption of nutrients from food. NCWS is a condition in which individuals report improvement of symptoms following the elimination of gluten from their diet. This diagnosis is only given after both celiac disease and wheat allergy are excluded.

How to read a label for gluten

Please check labels prior to consuming a product to ensure a safe gluten-free diet.

If a product is labeled “gluten free,” it is safe for people with celiac disease.

Third-party certifications exist to monitor manufacturers, but thus far research shows that both labeled and certified gluten-free foods are safe for people with celiac disease.

When a product is not labeled “gluten free,” you can determine if it’s safe to eat by reading the ingredients label:

  • Read the “contains” allergen statement at the bottom of the label.
  • If wheat is listed in the “contains” statement, the product is not gluten free.
  • If wheat is NOT listed in the “contains” statement, you must look for the following ingredients:
    • Always avoid:
      • Wheat, wheat starch
      • Rye
      • Barley, brewer’s yeast
      • Malt extract, malt vinegar, malt flavor
    • Avoid if product is not labeled gluten free:
      • Oats, oat bran, oat flour
      • Yeast (autolyzed or extract)
      • Smoke flavor from barley
      • Natural flavor from barley

Voluntary advisory statements

  • “May contain wheat” and “processed in a facility/on equipment that processes wheat” are voluntary statements NOT regulated by the U.S. Food and Drug Administration (FDA).
    • Research indicates that these labels are unreliable. Many products without the advisory statement are just as likely to unsafe for people with celiac disease as products with the advisory statement. Gluten contamination was found most often in products containing oats and with an advisory statement, which is why oats should only be consumed when labeled “gluten-free.”
  • Products labeled “gluten free” and with a voluntary advisory statement are safe for people with celiac disease.


  • Over-the-counter medicines must follow the above FDA labeling rules. Read the inactive ingredients on the package; if it contains wheat, barley or rye as any of the ingredients in #3, it is not gluten free.
  • Prescription medicines are not required to disclose allergens. Inactive ingredients should be checked for gluten content.

Dietary supplements

  • Dietary supplements must follow the above FDA labeling rules.
  • Supplements should be labeled gluten free, when possible, to avoid gluten contamination.


  • Alcoholic beverages labeled “gluten free” are safe to include in a gluten-free diet.
  • Those labeled “gluten removed” or “processed to remove gluten” are not safe for those with celiac disease.
  • Wine, fruit cider (without barley malt) and distilled liquor are all gluten free.
  • Beer and other malted beverages with barley are not safe for people on a gluten-free diet.

Do not start the gluten-free diet until your gastroenterologist (GI) or GI-expert dietitian tells you to and gives you instructions on how to follow the diet the right way.

Resources for label reading

Now it is time to meet with a GI-expert dietitian. To get more information about this topic, find a dietitian in your area using our Find a Health Care Provider tool.

Written by

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Janelle Smith, RD, and Sadie Nagle, RD
DIGID Disorders of the Brain Gut Interaction Workgroup ©2021