Irish scientists have made an important research discovery on how vitamin A, found in green and root vegetables, can protect against inflammatory bowel disease (IBD). Inflammatory bowel disease includes Crohn’s disease and ulcerative colitis, and it affects over 15,000 people in Ireland. The damaging inflammation in these conditions is assisted by immune cells that penetrate the gut tissue and are activated locally by bacteria normally resident in our gastrointestinal tracts. According to researchers at TCD, the main function of the immune system is to protect from infection with disease-causing bacteria and viruses, but these responses must be evenly balanced to prevent them from causing damage from inflammation. However in certain individuals, genetic or environmental influences can upset the balance, leading to excessive inflammation and serious conditions like IBD. A TCD research team led by Prof Kingston Mills has discovered that administration of retinoic acid, a dietary molecule of vitamin A, can protect mice against intestinal inflammation. Administering retinoic acid was found to to reduce the damaging effect of the gut bacteria and to promote recovery of the damaged tissue in the intestine. Professor Mills said the new finding provides important new information on the immune system and how its imbalance can lead to inflammatory diseases, such as ulcerative colitis and Crohn’s disease.