My skin is sensitive to some deodorants, so I use as little of these as possible and compensate by washing frequently. I have noticed that less time passes after a simple wash of the upper part of my body before I start to smell, than after a complete shower.
My theory is that, after a localised wash, germs are migrating across my skin from unwashed areas, and restarting the body odour more quickly. After a complete shower, the germs have been more-or-less equally decimated everywhere, and take longer to restore themselves.
So, my question: do germs or other lifeforms migrate across our skin, and, if so, how quickly? And is it faster to use the subway: in other words, go into the body and hitch a lift on some convenient blood cell?
Is there a natural ecosystem of the skin? Are we in danger of breeding soap-resistant germs?
And what of these antibacterial dish-detergents and such that have been so heavily promoted in the past few years? Won’t they help to breed stronger bacteria in the long run?
In regards to your last couple questions…yes, anti-bacterial soaps/detergents will promote heartier bacteria in the long-run. This problem is beginning to be seen with the over-use of antibiotics. The weaker/susceptible bacteria are killed, thereby leaving the stronger/resistant bacteria more resources to propogate from. Plus, bacterial populations have the capacity to develop resistances over time.
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So, my question: do germs or other lifeforms migrate across our skin, and, if so, how quickly?
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The bacteria don’t migrate, they muliply.
Every inch of your skin is covered by beneficial bacteria known as the natural flora. When you wash your skin with any kind of soap, you are taking off the top most layers of dead skin cells and the bacteria that are sitting on those cells. As the bacteria that remain on your skin divide and grow they slowly restore this natural flora.
No, this doesn’t happen. In fact while the bacteria on your skin is beneficial while it’s on your skin, it can create a nasty infection if it enters your blood stream.
Absolutely. The bacteria on your skin are part of the first line of defense against pathogens. If your skin is colonized by “good” bacteria, “bad” bacteria don’t have room to settle down on it.
Phobos pretty much covered the antibacterial soap aspect. I personally think they are overkill. If you’re thorough and consistent (while stopping well short of obsessive-compulsive) with your washing, regular soap should do just fine.
Very few bacteria are motile, thus few of them are able to “move” anywhere of their own volition. There is however, movement known as “brownian motion” which is to say, molecules (usually fluid molecues water, blood, etc.) will push the little guys around making them appear motile.
So the answer to your question: Bacteria are not moving to different places of your body, they are growing there from the bacteria that didn’t get washed off, or that landed there from your clothes, the air, people you brushed up against…you get the picture. Bacteria grow very quickly in the absence of competition (E. coli doubles in roughly 20 minutes)
One of the reasons that you might notice an odor faster after a localized washing than a shower, is that by washing locally you are removing the natural flora of that particular area thereby allowing other, perhaps stinkier bacteria to fill that ecologial niche. When you shower entirely, the flora all returns at roughly the same time, thus there isn’t a noticable difference in the odor.
Personlly I don’t use antibacterial soap, although supposedly it’s a non-specific antibiotic so it doesn’t target the genome like an oral antibiotic would (usually these target the cellular membrane, much like alcohol or Lysol would) so bacterial shouldn’t mutate a resistance. I don’t use them for the same reson that I generally don’t use oral antibiotics, because the natural flora of your skin and gut prevent other, perhaps pathogenic, bacteria from taking their space.
I don’t believe germs can get through the skin; after all, one of its functions is to keep germs out. Germs get in through places where there is no skin like the mouth or eyes or cuts in the skin. They are, I would assume, carried along by the plasma current and don’t ride the blood cells. In any case, they can’t control where they are going.
I wasn’t aware that bacteria weren’t particularly mobile; I guess I had an idea that they’d crawl across the skin like caterpillars or something.
Are there any resources about the ecosystem of the skin?
I remember in grade nine I drew a cartoon speculating about an ecosystem of the teeth: set up a system of robust but harmless germs in the mouth that would displace the germs responsible for dental caries… so I wouldn’t have to brush. Heh.
Someone mentioned to me recently that the human body is a lot more porous that we tend to assume… and that it really is both a world of its own and complexly connected to the rest of the world.
She said that the cultural effects of our full realisation of this and its implications (especially WRT to our views of our connection to the rest of the world and the life in it) would ultimately be more important than the cultural effects of the “view of the Earth from outside” that the early space explorers gave us…