Research collaborators from Yale University and the University of Chicago say that their finding lends support to the ''hygiene hypothesis'' that exposure to an appropriate amount and composition of bacteria may be important to living a healthy life, and that diabetes and other autoimmune disorders may result from a lack of exposure to certain parasites and microbes.
While conducting experiments on mice, the researchers observed that exposure to certain bacteria would trigger an immune system response in the animals.
They said that the immune response they observed seemed to be what prevents autoimmune disorders, conditions where the immune system attacks healthy cells in the body.
In type 1 diabetes patients, the immune system attacks the beta cells in the pancreas, stopping a person's ability to detect glucose and produce insulin.
For their study, the researchers had used bacteria that are harmless microbes found in the human intestine.
Based on their observations, they came to the conclusion that safe, measured exposure to certain bacteria might lower the risk of immune disorders.
''This study outcome gives us a new avenue to explore,'' Nature magazine quoted Dr. Richard A. Insel, Executive Vice President of JDRF, which funded the study, as saying.
''And, with type 1 diabetes in the U.S. and many countries around the world at about a three per cent annual rate, every lead is significant. The research gives impetus to better understanding how the bacterial flora in our body influences host immune defenses and responses that provide resistance to the development of type 1 diabetes. This understanding may provide new therapeutic approaches to prevention,'' he added.
The researchers said their study involved such mice as would not develop diabetes under normal conditions. However, if raised in a germ-free environment, the mice developed diabetes, they added.
They said that the mice that were exposed to common intestinal bacteria maintained a lower risk for the disease.