Licking Swings and Kissing Dogs

It's a known fact that small children put everything in their mouth, which until recently was thought to be a bad thing.  A new study suggests however that "early exposure to microbes is essential for normal immune development, supporting the so-called “hygiene hypothesis” which states that lack of such exposure leads to an increased risk of autoimmune diseases. Specifically, the study found that early-life microbe exposure decreases the number of inflammatory immune cells in the lungs and colon, lowering susceptibility to asthma and inflammatory bowel diseases later in life"(Scudellari).  This study could help explain why there is an increase of autoimmune disease in countries that use a lot of antibiotics.  Not much is known about when people should be exposes to microbes, but evidence suggests that it should be when people are young and that this exposure can prevent asthma and ulcerative colitis.  Scientists at Harvard performed a study on mice and found that the mice that were in a sterile environment were more susceptible to both diseases than those that were exposed to microbes.  One of the scientists says, "it does fit the “hygiene hypothesis,” he said, which proposes that the increasing occurrence of asthma and other inflammatory diseases in the developed world may be due to a reduced exposure to microbes early in life. But most importantly, future studies of human microbiota and the immune system should zero in on early childhood, he emphasized. “It’s quite important to focus on this early period," (Scudellari). http://the-scientist.com/2012/03/22/let-them-eat-dirt/