Americans are confused about gluten. Very confused.
Over one and a half million people in the U.S. are on a gluten-free diet, according to a Mayo Clinic study, even though they have no medical need for it.
A similar number of Americans have good reason to avoid gluten, but they are unaware they have celiac disease.
Celiac disease is a painful condition that damages the lining of the small intestine and prevents it from absorbing nutrients from food. The damage is caused by an allergic reaction from eating gluten, a protein found in wheat, barley, rye, oats and rice. Symptoms include abdominal pain, constipation and inflammation.
About 1.8 million Americans have celiac disease, but over 75% of them (1.4 million) are unaware that they have it, according to the Mayo Clinic study being published in the American Journal of Gastroenterology.
“This provides proof that this disease is common in the United States,” says co-author Joseph Murray, MD, a Mayo Clinic gastroenterologist. “If you detect one person for every five or six (who have it), we aren’t doing a very good job detecting celiac disease.”
Gluten-free food was once hard to find in stores, but the largest food companies in the world now include gluten-free products as a significant part of their marketing. Sales of gluten-free foods are expected to reach $5 billion by 2015, according to food and beverage industry researcher. In their rush to appeal to health conscious consumers, some companies are putting gluten-free labels on popular food products that never contained gluten in the first place.
The hype about gluten has alarmed so many Americans that many wrongly believe gluten is bad for them. Mayo Clinic researchers say 1.6 million people in the U.S. are on a gluten-free diet even though they haven’t been diagnosed with celiac disease.
There are a lot of people on a gluten-free diet, and it’s not clear what the medical need for that is,” said Dr. Murray, who adds that about 80 percent of the people on a gluten-free diet do so without a diagnosis of celiac disease. “It is important if someone thinks they might have celiac disease that they be tested first before they go on the diet. “
Other researchers have estimated the rate of diagnosed and undiagnosed celiac disease at similar levels prior to this study, but according to the Mayo Clinic this is the most definitive study on the issue.
To determine its prevalence, researchers combined blood tests confirming celiac disease with results from a nationwide survey conducted by the Centers for Disease Control and Prevention. The survey, designed to assess the health and nutrition of adults and children, is unique in that it combines interviews and physical examinations.
Researchers found that celiac disease is much more common in Caucasians.
“In fact, virtually all the individuals we found were non-Hispanic Caucasians,” says co-author Alberto Rubio-Tapia, MD, a Mayo Clinic gastroenterologist. The study found the rate of celiac disease in the U.S. is similar to that in several European countries.