The Medicine Cabinet: Ask the Harvard Experts
Q: I seem to be very sensitive to gluten. My doctor tested me for celiac disease and it came back negative. Will you please provide some insight into this paradox?
A: It’s not really a paradox. There are many people who experience a variety of symptoms from ingesting gluten, but like you they don’t have celiac disease.
In celiac disease, the immune system attacks the lining of the small intestine when you ingest gluten. Celiac disease symptoms are many and varied. But the ones most people report are gas, bloating, diarrhea, constipation, joint pain, headache and fatigue.
Celiac disease also damages the nutrient-absorbing fingerlike projections, called villi, on the intestinal wall. The results are weight loss and malnutrition. Diagnosing celiac disease requires a blood test and sometimes a biopsy, in which a small sample is snipped from the intestinal wall and checked under a microscope for damage.
The treatment for celiac disease is adopting a completely gluten-free diet. This stops the harmful allergic reaction in your gut and allows the intestinal lining to heal.
People with celiac disease-like symptoms who don’t test positive for the condition may end up diagnosed with gluten sensitivity. What actually causes the symptoms of gluten sensitivity remains unknown.
While the symptoms and treatment of celiac disease and gluten sensitivity can be similar, there is an important difference. For those with celiac disease, even a crumb of food with gluten can cause illness and intestinal damage, so managing the disease means zero tolerance for gluten.
In contrast, a gluten-sensitive individual may feel unwell if some gluten sneaks through, but there is no long-term physical harm. Many people with gluten sensitivity find they can have a bit of gluten without problems. While too much triggers symptoms.
It’s important to pay attention to nutritional quality when going gluten-free. Gluten-free diets can be low in certain nutrients. Gluten containing foods often contain lots of B vitamins, fiber and a fair amount of protein.
Also, be skeptical about claims that gluten-free eating promotes weight loss or “detoxifies” the body. Not true. There is nothing inherently unhealthy about gluten.
(Howard LeWine, M.D. is an internist at Brigham and Women’s Hospital in Boston and assistant professor at Harvard Medical School. For additional consumer health information, please visit www.health.harvard.edu.)