OVER 7,000 strong and growing, community farmers’ markets are being heralded as a panacea for what ails our sick nation. The smell of fresh, earthy goodness is the reason environmentalists approve of them, locavores can’t live without them, and the first lady has hitched her vegetable cart crusade to them. As health-giving as those bundles of mouthwatering leafy greens and crates of plump tomatoes are, the greatest social contribution of the farmers’ market may be its role as a delivery vehicle for putting dirt back into the American diet and in the process, reacquainting the human immune system with some “old friends.”

Increasing evidence suggests that the alarming rise in allergic and autoimmune disorders during the past few decades is at least partly attributable to our lack of exposure to microorganisms that once covered our food and us. As nature’s blanket, the potentially pathogenic and benign microorganisms associated with the dirt that once covered every aspect of our preindustrial day guaranteed a time-honored co-evolutionary process that established “normal” background levels and kept our bodies from overreacting to foreign bodies. This research suggests that reintroducing some of the organisms from the mud and water of our natural world would help avoid an overreaction of an otherwise healthy immune response that results in such chronic diseases as Type 1 diabetes, inflammatory bowel disease, multiple sclerosis and a host of allergic disorders.

Read more at NYT