Diets high in saturated milk fats, found in processed foods and sweets, may increase the risk of developing immune disorders like inflammatory bowel disease in those who are genetically predisposed, a study of mice found. About 60 percent of mice fed a diet high in saturated milk fats developed ulcerative colitis, an autoimmune inflammatory bowel disease, within six months, compared with about 25 to 30 percent of the animals who ate a low-fat diet or one high in polyunsaturated fats such as safflower oil, according to research online today in the journal Nature. The severity and extent of the colitis was much greater in the mice fed milk fats than those fed low-fat diets, the study found.