D: Hey Yaël, do you use antibacterial soap?

Y: Sometimes.

D: Why do you use it?

Y: Uhm, I don't know. I guess because it's a good way to get rid of bacteria.

D: Ah, but that's just it. Did you know that researchers have discovered that there are at least 250 kinds of bacteria that live on our skin? Some of the kinds they found were completely unknown.

Y: What? I should be using extra-strength antibacterial soap!

D: Actually, just the opposite. Bacteria are natural, even necessary tenants in human bodies. There are more bacterial cells in the human body than human cells. Way more, in fact.

Y: But isn't bacteria bad? Doesn't it cause disease?

D: Sometimes. But not all bacteria are bad for you. The bacteria in our bodies are there for a reason. For instance, bacteria in our intestines are important for digestion. And it's likely that the bacteria on our skin play important roles in keeping skin soft and enabling it to do what skin is supposed to do.

Y: So why is antibacterial soap so popular?

D: Good question. Maybe because we're obsessed with cleanliness. But it's impossible to completely rid the skin of bacteria, and in any case it wouldn't be a good idea to try. There's evidence that the bacteria that live in and on us help protect us from microbes that do cause infections. Getting rid of our natural bacteria could pave the way for harmful bacteria to move in.

Y: Good point. So sharing our bodies with bacteria is a good thing.

D: Yep. And given how many bacteria there are in our bodies, it's almost like they're making room for us.