Celiac disease is a chronic condition that occurs when gluten triggers an abnormal immune system response that damages the lining of the small intestine and prevents it from absorbing nutrients. People with celiac disease must avoid eating gluten--which is found in wheat, barley, rye, and possibly oats--for the rest of their lives.
Research studies in the United States and Europe indicate that celiac disease is significantly more common now than it was a few generations ago. Recent research by Joseph Murray, M.D., professor of medicine at the Mayo Clinic in Rochester, MN, and colleagues shows that this shift reflects an actual increase in prevalence, not merely a new awareness of the disease and more accurate diagnostic tools.
The researchers compared blood samples collected 50 years ago from more than 9,000 young adults, mostly men, at Warren Air Force Base in Wyoming with current samples from age-matched men. The investigators found that celiac disease is four times more common today than a half-century ago.
The increase cannot be a result of changes in the genetic factors that underlie celiac disease, Murray explained. “Of course, human genetics will change in response to the environment, but that change is extremely slow. It’s far more probable that the increase is due to an environmental change, and the most likely factor is a change involving the grain in our diets,” Murray said.
“Consumption of wheat has increased steadily over the past 50 years, but it still is less than what it was a century ago, so the issue is not simple consumption,” Murray noted. “It more likely involves the wheat itself, which has undergone extensive hybridization as a crop and undergoes dramatic changes during processing that involves oxidizers, new methods of yeasting, and other chemical processes. We have no idea what effect these changes may have on the immune system.”
A second environmental factor that may be contributing to the increase in celiac disease is what is known as the “hygiene hypothesis,” explained Murray. This theory proposes that the developing immune system has to be stimulated by exposure to infectious agents, bacteria, or parasites in order to develop properly. An increasingly clean environment reduces the number of factors that challenge and stimulate the developing immune system, making infants and children more susceptible to immune disorders and allergic diseases.
The hygiene hypothesis may account, in part, for the increases observed not only in celiac disease, but in other allergies and immune disorders. In fact, people with celiac disease are more likely to have other autoimmune disorders such as rheumatoid arthritis, systemic lupus erythematosus, Sjogren syndrome, Addison's disease, Hashimotos Thyroiditis, and Type 1 diabetes
Despite increasing rates of celiac disease, most Americans who have it probably don’t know it. It is estimated that one in every 100 Americans may be affected by celiac disease but only 5% of these people have ever been diagnosed as it’s symptoms are often misread.
Symptoms can vary in form and severity from person to person. The most telling symptoms in infants and children are gastrointestinal disturbances, irritable or fussy behavior or slowed growth and shorter than normal height for their age.
Many adults who have celiac disease do not have any symptoms, or have only mild ones such as abdominal pain, bloating, gas, indigestion, constipation or diarrhea which are often ignored or attributed to other causes.
While the exact cause of celiac disease is debatable, there may be a genetic component as people with a family history of celiac disease are at greater risk of developing it. The disease is also more common among Caucasians and persons of European ancestry and affects women more than men.
Celiac disease cannot be cured. However, symptoms will go away and lining of the intestines will heal if a lifelong gluten-free diet is followed.
It’s a good thing that today, September 13th, is officially "National Celiac Disease Awareness Day" as this disease may be one of the least understood and under diagnosed conditions affecting many of us.
National Institute of Diabetes and Digestive and Kidney Diseases
U.S. National Library of Medicine