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What Is Gluten?

Gluten is a protein found in wheat, barley and rye.

In medical and biological fields, “gluten” is actually an umbrella term for the combination of glutelin and prolamin proteins, which store nutrients in plants. They have different names depending on which grain is being discussed: in wheat, the glutelin is called glutenin and the prolamin is called gliadin; in barley the glutelin is called hordenin; in rye, secalins—you can see why it’s often easier to use “gluten.”

In baking, gluten is a unique and helpful protein, because it acts like a glue, holding a dough together and giving it an elastic texture. Once it’s baked, gluten is what gives bread a chewy, soft texture.

Oats, while they don’t have gluten, have a similar protein called avenin. Because the protein is so similar, a portion of those with celiac disease also react to oats.

What Foods Contain Gluten?

Gluten is found in wheat, barley and rye, so any product containing any of these three ingredients likely has gluten. Here are some foods to watch out for:

Wheat Products (Triticum)

  • Breads
  • Pastas
  • Cereals
  • Sauces
  • Candy Bars
  • Flour
  • Soups
  • Bakery Items

All species of wheat contain gluten, including durum, semolina, spelt, kamut, einkorn, faro and triticale (a hybrid of wheat and rye).

Barley Products (Hordeum vulgare)

  • Soups
  • Beer
  • Malt
  • Brewer’s Yeast
  • Cereals

Rye Products (Secale)

  • Certain Breads
  • Cereals
  • Beer
  • Rye Flour
  • Rye Milk
  • Any products containing triticale (a hybrid of wheat and rye).

Gluten is found in a wide variety of foods, even those you wouldn’t expect, such as soy sauce and even some french fries. It can be hidden in many foods as an additive, especially processed foods. Gluten can also sometimes be found in certain medications, personal hygiene products and more.

Wondering if a certain item is gluten-free? Learn to read labels, talk to manufacturers, and check out the Is It Gluten-Free section of our website.

Why is Gluten Bad for Some People?

A majority of people can tolerate eating gluten. However, those with celiac disease or non-celiac gluten sensitivity (sometimes referred to as “gluten sensitivity” or “gluten intolerance”) suffer a variety of symptoms after consuming gluten.

Celiac disease (also referred to as celiac sprue, non-tropical sprue, and gluten-sensitive enteropathy) is a serious, genetic autoimmune disorder triggered by consuming gluten. When a person with celiac disease eats gluten, the protein interferes with the absorption of nutrients from food by damaging a part of the small intestine called villi. Damaged villi make it nearly impossible for the body to absorb nutrients into the bloodstream, leading to malnutrition and a host of other problems including some cancers, thyroid disease, osteoporosis, infertility and the onset of other autoimmune diseases.
Learn more about celiac disease.

Non-Celiac Gluten Sensitivity has been coined to describe those individuals who cannot tolerate gluten and experience symptoms similar to those with celiac disease yet lack the same antibodies and intestinal damage as seen in celiac disease.

Gluten-Free Alternatives

There are a variety of grain, flour and starch alternatives that naturally do not contain gluten and thus can be consumed by those on a gluten-free diet. These include:

All grains are considered “high risk” for cross-contact because they are often grown, milled and manufactured near gluten-containing grains. “Cross-contact” occurs when a gluten-containing food touches a gluten-free food. Eating even tiny amounts of gluten can cause damage to the small intestine and prevent nutrients from being absorbed into the bloodstream. Whenever possible, purchase naturally gluten-free grains, flours and starches that are labeled gluten-free and certified gluten-free by a third party.

The Gluten-Free Diet

A gluten-free diet excludes all products containing wheat, barley and rye ingredients. Those who are gluten-free can still enjoy a healthy diet filled with fruits, vegetables, meats, poultry, fish, beans, legumes and most dairy products. Such ingredients are naturally gluten-free, and safe for individuals who do not have allergies to these respective food groups.

Learn more:

Gluten F.A.Q.

What is gluten?

Gluten is a protein found in wheat, barley and rye. Gluten acts like a glue and gives dough its elasticity and bread its chewy, soft texture.

Is gluten bad for you?

No, gluten isn’t unhealthy or dangerous for anyone except those with celiac disease, an autoimmune condition triggered by gluten, or those with non-celiac gluten sensitivity (NCGS).

Who should avoid gluten?

People who have been diagnosed with celiac disease must avoid gluten, because it damages their small intestine when they eat even a crumb. Those with non-celiac gluten sensitivity (NCGS) should also avoid gluten to alleviate symptoms. Those with IBS or on a low FODMAP diet may also experience relief from symptoms when they give up gluten.

Think you may have celiac disease?

Symptoms Checklist