Why Eating Dirt Is Good for Us

We scrub away germs to ensure good health, but in the long term, our "squeaky-clean" culture may be backfiring on us. Our immune systems developed to fend off a constant threat of invading organisms, learning to distinguish helpful and harmful invaders throughout life, writes Jeff Leach in the New York Times. Today, though, we deny our bodies the opportunity to grapple with those invaders, leading to a "minimally challenged and thus overreactive immune system." There's growing evidence that the phenomenon is contributing to ballooning allergies and autoimmune diseases.

If we faced some of our microbial "old friends" once again, research suggests it "would help avoid an overreaction of an otherwise healthy immune response," thus acting as a bulwark against diseases ranging from Type I diabetes to allergies. "The too-shiny produce and triple-washed and bagged leafy greens in our local grocery aisle are hardly recognized by our immune system as food," Leach points out. It's just another reason to go to your local farmer's market, where you might get a little more dirt in your dinner. Click through for Leach's full piece. (More dirt stories.)