Ever heard a friend or relative talk about going gluten-free? Or walked down the baking aisle at the grocery store and seen a box of gluten-free cake mix?

It seems like we’re hearing more and more about avoiding gluten lately. But why? What exactly is gluten, and why are so many people trying not to eat it?

Gluten is a type of protein found in wheat, rye and barley… the cereal grains that are ingredients in so many American foods. It’s the culprit in people with celiac disease, a genetically inherited condition that triggers the body’s immune response whenever gluten is consumed. About one in 133 people have the illness, according to the Celiac Disease Foundation.

A celiac patient’s immune response damages the intestinal villi [vill-eye], fine hairs in the small intestine that allow the body to absorb nutrients from food. Gas, bloating, weight loss and fatigue are a few of the symptoms that result. Too much damage to the villi can limit a person’s ability to take in nutrients from any foods, even those without gluten. If celiac disease goes untreated, it can lead to low body weight and malnourishment.

If you suspect you have celiac disease, see your doctor before eliminating gluten from your diet. Other serious conditions can cause similar symptoms, so he or she can help you reach a diagnosis.

If you do have celiac disease, take heart: Awareness of the condition is growing, as are gluten-free food options. Many people use flours made from other foods, such as almonds or corn, to make cakes, breads or pasta sans-gluten. Ready-made versions of these foods also are available in some grocery stores. Though it may be discouraging, a diagnosis of celiac disease doesn’t mean you’re doomed to a life of boring food.