Understanding Celiac Disease: Doctor Q&A
Celiac disease has garnered a lot of attention in recent years. Celiac is when the body has an autoimmune response to gluten, a protein found in wheat, barley and rye. Going gluten-free is the latest diet trend; however, it’s actually the medical treatment for celiac patients.
The buzz around celiac and gluten is spreading a lot of awareness—and misinformation. Dr. Stefano Guandalini, founder and medical director of the University of Chicago Celiac Disease Center, is on a mission to educate the public. The Celiac Disease Center, established in 2001, is at the forefront of celiac research and is working to find a cure for this condition. The research team is exploring many facets of the disease and recently launched a Celiac Microbiome Research Initiative.
Dr. Guandalini provides some insight on celiac disease and addresses common misconceptions.
How many people in the U.S. have diagnosed celiac?
Currently it is 1 percent of the general population. So that makes it a total of approximately 2.5 to 3 million people in the U.S. who have celiac disease. Seventeen percent of the celiac population is diagnosed, which leaves 83 percent not diagnosed. This is the most correct estimate and is an improvement over previous estimations. We used to think only about 3 to 5 percent of the celiac population was diagnosed. So there is an improvement, but we still have a long ways to go to improve the diagnosis rate.
Are people born with celiac or do they develop it later in life?
People are born with a genetic predisposition to celiac. Then, whether or not they would develop it, and at what age, depends on environmental circumstances, such as how much gluten they consume, their gut bacteria, and infections.
Why is a biopsy needed for proper celiac diagnosis?
We are in a time in which several academic bodies are re-examining this issue and coming up with different guidelines. New guidelines pop up almost every month in peer review journals, so it is a moving target. Sometimes antibodies in the bloodwork can come up positive, but that person does not have celiac. This is why you need a confirmatory test, which is a biopsy.
How does the biopsy work?
We recommend obtaining them during an upper endoscopy and it’s a pretty comfortable procedure. The recommendation, which is universally agreed upon, is to obtain at least four biopsies from the area that we define as the distal duodenum, which is three or four inches into the early portion of the small intestine. Then it’s also recommended to do one or two biopsies from the duodenum bulb, which is within the first inch of the small intestine. Once you take the biopsies, they are read by pathology and ranked by the Marsh celiac classification scale.
When should someone go gluten-free?
Rumors have spread around that you can make [a celiac] diagnosis with only a blood test. Some doctors make a diagnosis with one test only, putting patients on gluten-free diet with an unproven diagnosis. So this comes back in general to the point that people are jumping on the bandwagon of the gluten-free diet. Do not begin a gluten-free diet until you have been properly tested for celiac disease.
Celiac is an autoimmune disease, not a food allergy as is commonly believed. What’s the difference?
A food allergy is a condition that typically occurs almost immediately after ingesting the offending food. They imply production of specific antibodies, known as IGE. Food allergies are in general transient in children—most of them gradually acquire tolerance, but it’s not a guarantee. In autoimmune conditions, once they start, they are not transient; they are a permanent condition. The reaction is not an allergic reaction. It involves the intervention of T-cells and production of antibodies, which are directed against the constituents of the organ. In the case of celiac, the body produces antibodies against the epithelium of the intestines, so they destroy the intestines. So it’s a completely different ballpark.
It’s often reported celiac has gastrointestinal (GI) symptoms. But are there non-GI symptoms people can experience?
Yes. The most common GI symptoms are diarrhea, abdominal pain, vomiting, and malabsorption. This is how we came to know celiac disease. Then, slowly but surely, we came to realize there are other symptoms that can be as—if not more—prevalent. We suspect, currently, there has been a shift in the presentation of celiac disease. Not just because we are more aware, but because these have actually been documented. The lists of these symptoms are long, but they include short stature in children, anemia, and neurological manifestations such as recurring headaches, arthritis, joint pain, and osteoporosis. These can occur even without any gastroenterological manifestations.
Why are people following a gluten-free diet to treat other diseases besides celiac?
It’s now a fad. A vast majority of people who embrace a gluten-free diet don’t really need it. Even those who report feeling better not eating bread, pasta, or pizza—they need to say it might not be gluten but something else. It could be a different protein in wheat. We have zero evidence that gluten is causing anything in anybody outside of celiac disease and wheat allergy. People often blame gluten because it’s known to be toxic in celiac patients.
What is gluten sensitivity?
We cannot say gluten is causing symptoms in people who define themselves as having nonceliac gluten sensitivity. The term is a misnomer; it should be abandoned. These events are self-reported. No tests are showing abnormalities in these patients. We should stop talking about something that we can’t even define. We don’t know what is causing this. We need to do proper experiments to determine what is wrong with these people.
Can going gluten-free harm someone who doesn’t have celiac?
It’s not the healthiest diet, as people seem to believe. The negative impact is you might have more constipation because you’re eating less fiber. Products manufactured to be gluten-free are not enriched in vitamins, so there are risks. If you eat a natural gluten-free diet the risks are minimal—rice, potato, corn, fruit, vegetables, meats. But the problem is when you rely heavily on manufactured gluten-free products, which are refined, which are highly processed and don’t contain fiber.