Inside
job Teams of microbes pull strings in the human body
You are surrounded, grossly out- numbered and being manipu- lated from within. Teeming masses of bacteria
are in your mouth, on your skin, up your
nose and on the surface of your eye, in
your stomach, deep in your bowels and
well, just about everywhere. In fact, the
number of bacterial cells you harbor
exceeds the count of your own body’s
cells by 10-to- 1.
But don’t be too hasty in reaching for
the disinfectant. You can’t wash these
microbes away. Nor should you. They
are — for the most part — friendly. So
friendly that many scientists now view
humans as conglomerate superorganisms
composed of thousands of species.
Scientists have dubbed this internal flora
the “microbiome,” a nod to the little ecosystems that have blossomed in the body
throughout human evolution.
These microbes are no mere hitch-hikers. They’re hard at work cleaning up
your insides and pumping out compounds
that have all kinds of effects on health,
development and perhaps even some
behavior, emerging evidence suggests.
While humans are definitely in a rela-
tionship with microbes, the status of that
relationship is probably best described
as “It’s complicated.” On the positive
side, studies show that intestinal bac-
teria help to digest food, provide key
vitamins and even feed cells lining the
intestines. Friendly microbes in the gut
and vagina and on the skin can protect
against infections from disease-causing
bacteria and educate the immune sys-
tem. Some bacteria in the mouth even
help prevent tooth decay.
