New clue in coeliac disease puzzle: Cause of oat toxicity explained
Researchers have identified why some people with celiac disease show an immune response after eating oats.
As many as one in 60 women and one in 80 men in Australia have coeliac disease, an autoimmune condition caused by consuming gluten, a protein found in wheat, rye and barley. The abnormal immune response to gluten damages the small intestine and is associated with gastrointestinal symptoms including vomiting and diarrhea, lethargy, and an increased risk of osteoporosis and cancer. People with coeliac disease must adhere to a lifelong gluten free diet that excludes wheat, barley and rye.
The question of whether oats are toxic for people with coeliac disease is controversial, but because oats contain proteins, called avenins, that are similar to gluten, oats are excluded from the gluten-free diet in Australia.
Researchers from the Walter and Eliza Hall Institute, Monash University and US biotechnology company ImmusanT, led the 10-year study, published this month in the Journal of Autoimmunity. They revealed that oat consumption triggered an immune response in eight per cent of the 73 participants with coeliac disease.
Walter and Eliza Hall Institute researcher Dr Melinda Hardy said the research was the first of its kind to comprehensively profile immune responses to oats in people with celiac disease. “The significance of previous studies performed in test tubes was unclear,” she said. “By studying people with coeliac disease who had eaten oats, we were able to undertake a detailed profile of the resultant immune response in their blood stream. Our study was able to establish the parts of oat avenins that cause an immune response in people with coeliac disease.”
Dr Jason Tye-Din, head of coeliac research at the Walter and Eliza Hall Institute and a gastroenterologist at The Royal Melbourne Hospital, said the study showed oats were well tolerated by most people with coeliac disease, but in a proportion of people with coeliac disease oat consumption could trigger immune responses similar to those caused by eating barley.