Scientists Find Wheat Protein May Cause Coeliac Disease and Diabetes
Gluten, a protein found in wheat, is known to cause food allergies and has been linked to conditions such as Irritable Bowel Syndrome and Crohn’s Disease. Coeliac disease, an autoimmune condition caused by sensitivity to gliadin, a protein (gluten) found in wheat, and can have serious symptoms ranging from chronic diarrhea to weight loss and anemia. The condition causes chronic inflammation of the section of the intestinal tract between the stomach and the large intestine, damaging the structures on the intestine wall that absorb nutrients from ingested food. Between 0.5 and 1% of Americans are affected by the disease. The only cure for the condition is to follow a diet that does not include gluten, and the majority of food stores now carry large ranges of gluten free foods such as bread and cakes.
Type I diabetes occurs typically in children and young people when the pancreas produces insufficient insulin to cope with the levels of blood sugar after eating. This is also an autoimmune condition, in which the beta cells in the pancreas are damaged by an immune response.
Now researchers in theUKhave discovered that both these conditions have a common genetic origin, suggesting they may be brought on by environmental factors. They say their findings have brought them to conclude that gluten is the common factor that triggers both diseases.
The study, partly funded by the Juvenile Diabetes Research Foundation and carried out at the University of Cambridge, Barts, and the London School of Medicine and Dentistry, was carried out using data from nearly 20,000 tissue samples. Genetic testing showed that there were similarities between diabetes and coeliac disease, with seven shared chromosome regions. Researchers believe these defective chromosomes cause the immune system to attack the pancreatic beta cells in diabetics and the small intestine in coeliac sufferers.
Although more research is needed to understand how genetic and environmental factors combine to cause the conditions, it scientists are confident gluten was implicated in the development of type 1 diabetes. Gluten, which is made up from the proteins gliadin and glutelin, is present in the endosperm of many types of seeds from the grass family, but in modern triticales, hybridizing over centuries has produced higher gluten content. Many wheat species are especially high in gluten as they are grown to produce flours suitable for bread making.
Rice, maize and other grains may contain gluten, but lack the gluten component gliadin, which seems to be the factor that causes allergic and immune reactions. Coeliac disease is uncommon in southernChina, where rice is the main staple of the diet, but less uncommon in the north, where more wheat is eaten. Type I diabetes is less common in China, at 0.1 per 1000,000 per year, compared to up to 20 per 100,000 per year in some western countries. Type 2 diabetes is now hugely on the increase as the Chinese adopt western lifestyles and eating habits.