Genetic factors cannot fully explain the development of diabetes. If genetic factors were the only cause of type 1 diabetes, such an increase in cases would take at least 400 years. Some researchers believe one or more viral infections may trigger the disease in genetically susceptible individuals. T cells and antibodies are tricked by this resemblance into attacking the beta protein as well as the virus. Among the viruses under scrutiny are enteric viruses, which attack the intestinal tract.
Coxsackieviruses are an enteric virus of particular interest.
Cow's Milk Some studies have found a slightly increased risk for type 1 diabetes in children with risk factors for diabetes and who are exposed to cow's milk in very early infancy. One study found that children fed cow's milk in the first eight days of life had twice the risk as those on breast milk. Some experts believe that this higher risk occurs only in children who are genetically susceptible to an impaired immune response to dietary proteins. Such children may also be at increased risk for other digestive diseases, such as celiac sprue. National differences in risk that parallel different milk proteins also suggest that not all cow's milk is the same and some proteins carry higher risks.