If you are a mom or dad, and feel guilty about not cleaning your house often enough, relax. You've been doing the best thing for your kids' health.

A USA Today news article, which includes informative links, states:

"What we've learned is that it may, in fact, be important to be exposed early on to a sufficient quantity of allergy-causing substances to train the immune system that they are not a threat," says Andy Saxon of the University of California-Los Angeles.

"Between the ages of zero and 12, you're learning to read, you're learning to write, and your immune system is learning to react to things. Part of that is learning to limit reactivity," says Joel Weinstock of Tufts New England Medical Center.