Celiac disease (also called gluten enteropathy) is an intestinal disorder that results from an abnormal immunological reaction to gluten, a protein found in wheat, barley, rye, and, to a lesser extent, oats.
In addition to damaging the lining of the small intestine, celiac disease can sometimes affect other parts of the body, such as the pancreas (increasing the risk of diabetes), the thyroid gland (increasing the risk of thyroid disease), and the nervous system (increasing the risk of peripheral neuropathies and other neurological disorders). Occasionally, such damage occurs only in one or more of these parts of the body in the absence of damage to the intestines.
What are the symptoms of celiac disease?
Celiac disease may not cause symptoms in some people. However, others may have a history of frequent diarrhea; pale, foul-smelling, bulky stools; abdominal pain, gas, and bloating; weight loss; fatigue; canker sores; muscle cramps; delayed growth or short stature; bone and joint pain; seizures; painful skin rash; or infertility. Microscopic examination of the small-intestinal lining reveals severe damage, especially in the jejunum (the central portion of the small intestines). People with untreated celiac disease may eventually experience malaise and weight loss and have an increased risk of developing anemia, osteoporosis, osteomalacia, and certain types of cancer. In addition to physical symptoms, some people may experience emotional disturbances, including feelings of anxiety and depression.
Dietary changes that may be helpful for celiac disease
All doctors agree that consumption of the gluten-containing grains wheat, barley, and rye must be avoided in all celiac patients. Less consensus exists regarding the advisability of eating or restricting oats and oat products. While oats contain a substance similar to gluten, modern research suggests that eating moderate amounts of oats does not cause problems for most people with celiac disease.1 In one of these reports, approximately 95% of people with celiac disease tolerated 50 grams (almost two ounces) of oats per day for up to 12 months.2
Strict avoidance of wheat, barley, and rye, and of foods containing ingredients derived from these grains, usually results in an improvement in gastrointestinal symptoms within a few weeks, although in some cases the improvement may take many months. Tests of absorptive function usually improve after a few months on a gluten-free diet.3
Many people with celiac disease become symptom-free when following gluten-free diets. Others, however, continue to experience symptoms, often resulting from the presence of trace amounts of gluten either permitted in some gluten-free diets or consumed by mistake. Such mistakes are easy to make because many processed foods contain small amounts of gluten. For people with residual symptoms, a diet that truly eliminates all gluten, followed by open and double-blind challenges, resulted in symptomatic improvement in 77% of those studied.4 A careful dietary analysis should ensure that all trace amounts of gluten are removed from the diet. If this fails to relieve symptoms after three months, then other food intolerances should be ruled out using an elimination diet.
Avoiding gluten may also reduce cancer risk. In one trial, 210 people with celiac disease were observed for 11 years. Those who followed a gluten-free diet had an incidence of cancer similar to that in the general population. However, those eating only a gluten-reduced diet or consuming a normal diet had an increased risk of developing cancer (mainly lymphomas and cancers of the mouth, pharynx, and esophagus).5
Children with untreated celiac disease have been reported to have abnormally low bone mineral density. However, after approximately one year on a gluten-free diet, bone mineral density increased rapidly and approximated the level seen in healthy children.6 Long-term adherence to a gluten-free diet ensures normal bone density and is an important preventive measure in young people with celiac disease.7
Adults with celiac disease also have significantly lower bone mineral density than do healthy adults. After consumption of a gluten-free diet for one year, bone mineral density of the hip and lumbar spine has been reported to increase by an average of more than 15%.8
Infertility, which is common among people with celiac disease, has been reportedly reversed in both men and women after commencement of a gluten-free diet.9
Some people with celiac disease may be intolerant to other foods, in addition to gluten. Foods that have been reported to trigger symptoms include cows’milk10 and soy.11 12 13
Lifestyle changes that may be helpful for celiac disease
In one study, children who were breast-fed for less than 30 days were four times more likely to develop celiac disease, compared with children who were breast-fed for more than 30 days.14 Although this study does not prove that breast-feeding prevents the development of celiac disease, it is consistent with other research showing that breast-feeding promotes a healthier gastrointestinal tract than does formula-feeding.15
Nutritional supplements that may be helpful for celiac disease
The malabsorption that occurs in celiac disease can lead to multiple nutritional deficiencies. The most common nutritional problems in people with celiac disease include deficiencies of essential fatty acids, iron, vitamin D, vitamin K, calcium, magnesium, and folic acid.16 Zinc malabsorption also occurs frequently in celiac disease17 and may result in zinc deficiency, even in people who are otherwise in remission.18 People with newly diagnosed celiac disease should be assessed for nutritional deficiencies by a doctor. Celiac patients who have not yet completely recovered should supplement with a high-potency multivitamin-mineral. Some patients may require even higher amounts of some of these vitamins and minerals—an issue that should be discussed with their healthcare practitioner. Evidence of a nutrient deficiency in a celiac patient is a clear indication for supplementation with that nutrient.
After commencement of a gluten-free diet, overall nutritional status gradually improves. However, deficiencies of some nutrients may persist, even in people who are strictly avoiding gluten. For example, magnesium deficiency was found in 8 of 23 adults with celiac disease who had been following a gluten-free diet and were symptom-free. When these adults were supplemented with magnesium for two years, their bone mineral density increased significantly.19
In another study, six people with diet-treated celiac disease had abnormal dark-adaptation tests (indicative of “night blindness”), even though some were taking a multivitamin that contained vitamin A. Some of these people showed an improvement in dark adaptation after receiving larger amounts of vitamin A, either orally or by injection.20 People with celiac disease should discuss the possibility of vitamin A deficiency with a healthcare practitioner before taking vitamin A supplements.
Malabsorption-induced depletion of vitamin D can lead to osteomalacia (defective bone mineralization) in people with celiac disease.21 Although supplementation with vitamin D appears to increase bone density, the excess risk of bone fracture may not be entirely eliminated.
It is possible that subtle deficiencies of other nutrients may exist in people with celiac disease who are on a gluten-free diet and are in remission. People who are not strictly avoiding gluten are likely to have more severe deficiencies. Because of the complexity of this condition and the multiple nutritional factors involved, people with celiac disease should be under the care of a doctor. Some doctors may recommend use of nutritional supplements, including a high-potency multivitamin-mineral supplement, to reduce the risk of future deficiencies. No controlled trials have investigated the value of supplements in the minority of celiac disease patients who do not go into remission in response to a gluten-free diet.22
In one trial, 11 people with celiac disease suffered from persistent depression despite being on a gluten-free diet for more than two years. However, after supplementation with vitamin B6 (80 mg per day) for six months, the depression disappeared.23
People with celiac disease often do not produce adequate digestive secretions from the pancreas, including lipase enzymes24 In a double-blind trial, children with celiac disease who received a pancreatic enzyme supplement along with a gluten-free diet gained significantly more weight in the first month than those treated with only a gluten-free diet.25 However, this benefit disappeared in the second month, suggesting enzyme supplements may only be useful at the beginning of dietary treatment.
Are there any side effects or interactions with celiac disease?
Refer to the individual supplement for information about any side effects or interactions.