http://en.wikipedia.org/wiki/Hygiene_hypothesis http://en.wikipedia.org/wiki/Hygiene_hypothesis The Hygiene Hypothesis is the theory that fewer infectious agen

http://en.wikipedia.org/wiki/Hygiene_hypothesis http://en.wikipedia.org/wiki/Hygiene_hypothesis The Hygiene Hypothesis is the theory that fewer infectious agents you encounter as a child will boost the chances you'll have allergenic problems. The reasoning behind this is that your immune system isn't getting the same inputs or "training sets" as they would have 200 years ago. Since it isn't getting primed with actual infectious material, your immune system starts reacting adversely to silly things like pollen, peanuts, etc.