Celiac Disease

Celiac disease is a lifelong autoimmune disorder that damages the small intestine, can cause long-lasting digestive problems, can interfere with the body's absorption of nutrients, and may cause injury to the gut, skin, liver, joints, uterus, and other organs. It is triggered by eating foods with gluten, which is a protein found in wheat, barley, and rye.

As many as one in 141 people in the United States has celiac disease, although most are not aware of it. It is more common in Caucasians and more often diagnosed in females. It affects children and adults in all parts of the world and is more likely to develop in people who have relatives with the disease. Celiac disease is also more common among people with such other diseases as type 1 diabetes, Down syndrome, and Turner syndrome.

People of any age can be diagnosed with celiac disease, but there are two common peaks for diagnosis—one between 8–15 months (which is shortly after infants usually begin eating wheat products) and another between 30–40 years in adults.

Celiac disease is an autoimmune disease. Whenever immune system cells in the body sense the presence of foreign material, they produce proteins called antibodies to disable the foreign material. In an autoimmune disease, the body treats some of its own cells as foreign and attacks them. Celiac disease is also classified as a malabsorption disease because the cells that are damaged by the body's immune system are cells of the villi lining the small intestine, where most nutrients are absorbed. When these cells are damaged, the villi flatten out, decreasing the surface area available for absorption. Nutrients are not properly absorbed, and vitamin and mineral deficiencies often develop.

The symptoms of celiac disease were described as early as 1888, but it was not until the 1950s that physicians began to understand what caused the disease. A Dutch pediatrician, W. K. Dicke, was the first person to make the connection between the consumption of foods containing wheat and symptoms of celiac disease. By the twenty-first century, researchers knew that the problem substance is gluten, a protein found in wheat, rye, barley, and any products made from these grains such as flour, bread, pasta, and beer. Many pre-packaged foods as well as lip balms and lipsticks, hair and skin products, toothpastes, vitamin and nutrient supplements, and, rarely, medicines contain gluten.

Symptoms of celiac disease are varied. Some people have the disease (as diagnosed by samples that show damage to the small intestine), but they show no symptoms. Others go along for years with annoying or intermittent symptoms, and some, especially children, show severe symptoms of malnutrition and stunted growth despite eating a healthy diet. Symptoms are similar to those of other, more common, digestive diseases. Often, celiac disease is initially misdiagnosed.

In children, digestive symptoms are more common than adults and can include:

Children with celiac disease who are unable to absorb adequate nutrients can have growth and development issues that include:

Adults are more likely than children to have at least one of the following:

Celiac disease can be difficult to diagnose because its symptoms are similar to those of so many other diseases. Often, it is initially misdiagnosed as irritable bowel syndrome, lactose intolerance, or Crohn's disease. A doctor can diagnose celiac disease with a medical and family history, physical exam, and tests, which may include blood tests, genetic tests, and biopsy.

People with celiac disease have immune systems that produce higher than normal levels of certain antibodies. Blood tests may detect abnormal levels of these antibodies. If blood tests are positive, an upper GI endoscopy of the small intestine is done. Endoscopies allow a doctor to see if there is damage to villi. During this procedure, the doctor also removes small tissue samples (biopsies) from the intestinal lining in order to look for cell damage under the microscope. Presence of a specific type of damage is a positive diagnosis for celiac disease.

No cure is known for celiac disease. The only treatment is life-long avoidance of any foods that contain gluten. This means not eating foods that contain wheat, rye, and barley, such as bread or baked goods, pizza, spaghetti, beer, and many processed foods that use flour as a thickening agent. Oats are often eliminated as well, mostly due to cross-contamination. When individuals fail to improve on a gluten-free diet, it is sometimes because they are unintentionally consuming sources of hidden gluten. A few people on truly gluten-free diets do not improve. They can be treated with corticosteroid drugs to reduce inflammation, but this does not heal the intestine.

By the beginning of 2018, clinical trials concerning treatment of celiac disease were underway with the goal of finding medications to improve the prognosis of celiac disease or enable people to eat a diet that includes gluten. Patients interested in participating in a clinical trial at no cost can find a list of trials currently enrolling volunteers at http://www.clinicaltrials.gov .

Individuals newly diagnosed with celiac disease may find it helpful to meet with a nutritionist or dietitian to aid with meal planning. Two issues need to be addressed. First, determining what is safe to eat, and second, learning how to get the right balance of nutrients in a gluten-free diet. Complicating matters, damage to the intestines may make some people lactose intolerant, so that they either cannot eat or must limit dairy products in their diet.

Many cookbooks are available to help people on a gluten-free diet. Home cooks must learn to substitute ingredients, such as cornstarch and rice flour, for wheat flour in their foods. An increasing number of gluten-free foods are available commercially. These often cost more than their gluten-containing counterparts. Foods people with celiac disease can safely eat include:

Learning how to read food labels is very important. In 2013, the United States Food and Drug Administration (FDA) published a final rule that defined the standards for foods labeled as gluten-free. The rule became effective August 5, 2015. Labeling is voluntary, and it ensures the packaged food meets specific characteristics for a food to bear this claim. People with celiac disease should still read ingredient labels to make informed decisions about what they are eating. For packaged foods not labeled as gluten-free, people need to be alert to hidden sources of gluten that often serve as binders or thickeners in commercially prepared foods. Some of these non-obvious sources of gluten that may appear on food labels are:

Some brands of commercially prepared french fries, potato chips, hot dogs, meatballs, gravy mixes, soups, soy sauce, and candy contain these hidden sources of gluten. Others are gluten-free. A nutritionist and dietitian can help people with celiac disease learn to read labels accurately to distinguish foods that are safe for them.

Switching to a gluten-free diet requires major lifestyle changes. It can be especially hard on children and teens who want to be able to go out with their friends and eat pizza and fast food. Many people find internet support groups are helpful in making the transition to a gluten-free diet.

The intestines of people with celiac disease who go on a gluten-free diet heal. In children, the healing usually takes 3–6 months. In adults, healing can take two years. The intestinal villi remain intact and function properly so long as the diet remains free of gluten, but the disease is never cured.

People who are not diagnosed, or who do not stay on a gluten-free diet, face increased chances of developing cancer of the intestine. They may also develop osteoporosis because of poor calcium absorption. Other vitamin and mineral deficiencies may contribute to a multitude of health problems. Untreated pregnant women have higher than normal rates of miscarriage and babies born with birth defects, especially neural tube defects, which arise from inadequate amounts of folic acid. Untreated children may have stunted mental and physical growth.

Celiac disease is a genetic autoimmune disorder that cannot be prevented. Once diagnosed, the only way to prevent symptoms and complications is to follow a strictly gluten-free diet.

See also Anti-inflammatory diets ; Crohn's disease ; CSIRO Total Wellbeing diet ; Digestive diseases ; Food allergies ; Food labeling ; Gluten-free diet ; Inflammatory bowel disease ; Irritable bowel syndrome ; Malnutrition .