The next time you look in the mirror,
think about this: In many ways, you're
more microbe than human. There are 10
times more cells from microorganisms,
bacteria, viruses, fungi, than human cells
in and on our bodies.
And our genes are outnumbered a hundred to one by microbial genes.
Scientists even have a name for all these microbial genes:
The Human Microbiome.
Now, this might make a lot of people rush for the hand sanitizer,
but it turns out most of these microorganisms aren't bad
germs that
will make us sick,
most are good and without these good microbes
our bodies don't seem to do as well.
We don't seem to be as healthy and we actually might get sick more often.
So one question is: where do our microbiomes come from in the first place?
Well, like a lot of things, it starts with our mothers.
As the
infant passes through the birth canal,
it gets coated with microbes from the mom.
These microbes may kind of seed the baby with just the right mix.
Combined with
bacteria and breast milk and other
microbes we encounter early on, they seem
to slowly take shape in our first few years of life.
The overall mix of our
microbes becomes very personal,
sort of like a fingerprint or maybe a blood type.
But our microbes tend to resemble those of our parents and siblings
and may stay with us for much of our lives.
They may also be doing all sorts of things, such as educating our immune cells,
like this one: teaching them the difference between
things they should fight off,
bad bugs that might make us sick and things that
aren't a threat, like our good microbes.
When we're adults, microbes become our
first line of defense, fighting off germs
that try to invade our bodies, protecting
their turf while protecting our health.
Scientists have discovered they can even
spew out their own antibiotics.
The types of microbes in your body vary
depending on exactly where they live
like different ecosystems in nature.
There are wet places like our mouths,
noses and armpits, oily places like our
scalps and backs and dry places like our forearms.
Different species of microbes
have adapted to each of these habitats.
The biggest, most important microbial
habitat seems to be in the gut.
It's the most complex, the most diverse and
everything microbes are doing
everywhere else in our bodies- fighting off
infections, revving up and dampening down
our immune systems, signaling cells-
that's all happening in the gut in spades.
They even seem to help regulate
our metabolisms, how much energy we burn
and how much fat we store.
So if it's not
functioning properly for some reason
because of what we eat, antibiotics we
take, that may actually lead to all kinds
of diseases. Diseases like colon cancer,
colitis maybe even diabetes and obesity.
Some scientists think one reason a lot
of diseases are increasing is because
we've lost key gut microbes.
Our microbiomes look far less diverse
compared to those of people in less
developed countries and earlier
generations and remember how we get our
microbiomes in the first place:
from our mothers when we're born and from breast
milk? Well, some scientists think that too
many babies aren't getting that because
of all the c-sections and not enough
breastfeeding plus all the antibiotics
kids get these days and our obsession with cleanliness.
All this may help
explain why problems like asthma and
allergies have been soaring. Maybe
because our microbiomes never taught our
immune systems how to work the right way.
Maybe swallowing good microbes,
probiotics, could prevent and treat some diseases.
So could taking prebiotics,
essentially food that good microbes love.
We end our story with a reminder: this
research is really new.
We still have a lot to learn about what many of our
microbes are really doing but scientists
say that is getting clearer and clearer
that the tiny organisms all over our
bodies are essential to our health and
happiness.
