What Is a Gluten-Free Diet?

How to tell if gluten is affecting your digestive tract

In people with celiac disease, gluten can damage the digestive tract. It harms the small intestine’s villi. Villi are small, fingerlike projections that absorb nutrients from food. If the villi are harmed, the body can't absorb enough nutrients. You may start to feel stomach pain, indigestion, bloating, and other unpleasant symptoms. The disease can cause more serious conditions if not treated.

Healthcare providers advise a gluten-free diet based on whether you have celiac disease. This is based on blood test results and biopsy samples taken of the small intestine. If you have celiac disease, you need to stay away from all gluten forever. This is true even if you don't have symptoms. Common symptoms include:

• Joint pain and inflammation

• Digestive problems, including stomach pain and bloating

• Indigestion and acid reflux

• Constipation or diarrhea

• Tiredness (fatigue)

• Anxiety, mood swings, or depression

• Vitamin deficiencies

• Skin rashes and itching

• Infertility

• Recurring miscarriages

• Migraines

• Canker sores

• Tingling in the hands and feet

Treating gluten troubles with diet

Eating gluten can harm the small intestine and other tissues and organs in anyone with celiac disease. This can make it hard for you to absorb nutrients. Some people without celiac disease also have trouble tolerating gluten. Or they are sensitive to it.

Diet is the main way to treat gluten intolerance or gluten sensitivity. A big part of a gluten-free diet is to stay away from foods made with wheat, rye, or barley. This means most regular breads, pizza, cereals, pastas, cakes, and cookies. Many processed foods contain hidden gluten. The most common foods are soy sauce, gravies, canned soups, nutritional bars, barley malt, and veggie burgers. It can even be found in medicines, probiotics, vitamins, and supplements.

Foods, such as rice, potatoes, beans, corn, quinoa, some oats (that are labeled gluten free), nuts, fruits, vegetables, and some alcoholic beverages are naturally gluten-free.

But even products, such as lipstick or dental products, can contain gluten. If you have celiac disease, you'll need to become an expert at reading food and product labels. This is a skill that your healthcare provider, nutritionist, or a gluten-free support group can help with. This is because you need to follow the diet carefully and for the rest of your life. 

Be careful when replacing gluten foods with foods that are gluten-free. The National Institutes of Health (NIH) says that packaged gluten-free foods aren’t always better or healthier. In fact, some gluten-free foods are higher in fat, sugar, and total calories than foods with gluten. As with any diet, the variety of nutritious foods in your gluten-free diet will determine how healthy it is. If you do not have celiac disease but think you are gluten sensitive, speak with your healthcare provider about diets that may help to prevent an unnecessarily restrictive diet.

Protecting your health by going gluten-free

If you are living with a gluten sensitivity or intolerance, you may choose to stay away from or limit how much gluten you eat. If you have been diagnosed with celiac disease, you’ll need to work with your healthcare providers to make sure that you're getting enough vitamins and minerals. Your provider can let you know if you need to take any supplements to replace any missing nutrients. Be aware that some supplements are made with ingredients that contain gluten, so choose supplements carefully. The NIH provides a list of foods and other products containing gluten . The Celiac Disease Foundation also provides helpful information.

After you start on your gluten-free diet, your small intestine will start to repair the damage to its villi. After a while, your body will start absorbing food normally again and your digestive symptoms will begin to improve. Healing time will vary from person to person. You also should start to feel much better overall.

If you don't notice enough improvement, it's usually because you still have small amounts of gluten in your diet. Other conditions can also interfere with a gluten-free diet. These include irritable bowel syndrome, microscopic colitis, lactose intolerance, and bacterial overgrowth in the intestine. Talk with your healthcare provider regularly to keep track of your condition. Call your healthcare provider right away if you continue to have symptoms or side effects once you’re on a gluten-free diet. Rarely, the disease and symptoms continue even with a completely gluten-free diet. If this is the case, you will most likely need more testing.

Celiac disease is a life-long serious illness that can be managed through changes in your diet. Untreated celiac disease can lead to long-term (chronic) health problems. It can also increase your risk for certain cancers.