Unintended Consequences #4

In a previous post, I wrote about the tradeoffs facing the efforts of the Gates Foundation to eliminate polio. One of the surprising conjectures was that poor water quality might actually promote community resistance to polio.

That same "unexpected consequence" on a broader scale has been addressed today in the Wall Street Journal in an article entitled "Can a Dirt Do a Little Good?" . It points out that a child growing up in a health-conscious American city like San Francisco has a much better life expectancy than one growing up in a developing country such as Namibia or Mongolia, but that San Francisco child has a higher expectancy of diseases such as asthma, Type I diabetes, MS and other auto-immune diseases. The article profiles the possibility that our cleanliness may be a contributing factor to these diseases. The combined effect is reflected in overall survival rates: sanitation produces better childhood survival, but, as the article says, there's nothing inherently wrong with having your kids play in the dirt once in a while....it may actually be good for them.