Human skin supports many bacteria

By Tom Nordlie • Published: September 24th, 2009
Category: Health in a Heartbeat

You’ve heard the saying “your body is a temple.”

As far as your skin is concerned, it’s more like a city.

A study published recently in the journal Science shows that numerous bacteria colonize the skin. Different species grow in different places.

The researchers took bacterial samples from ten volunteers. They swabbed twenty areas, ranging from the back of the head to the bottom of the heel.

These areas fell into three groups, based on the environment they provided… dry, moist or greasy.

Researchers used genetic analysis to identify bacteria, and found more species than in previous studies where the bacteria were cultured.

That’s because culture-based studies are biased toward bacteria that readily grow under lab conditions.

Here, most bacteria came from three genera [JENN-err-uh], including Staphylococcus [STAFF-ill-oh-COCK-uss], a genus that includes the notorious antibiotic-resistant species M-R-S-A [“MERSA”].

On any given volunteer, different skin areas tended to harbor similar bacterial strains.

But bacteria types varied between volunteers, even when comparing skin from the same area of the body.

And a later study showed that the bacterial colony in one area on one volunteer might change over time, though some areas remained consistent.

These data may provide insights for dermatologists on two important issues… why some skin diseases tend to emerge at certain places, and how antibiotic-resistant skin diseases originate.

The skin is a first line of defense against many pathogens. So this research could provide answers on how to manage bacterial colonies.

In other words, planned growth might prevent some very undesirable developments.