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Speaker 1: Welcome to Brainstuff from house Stuff Works dot com where

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Speaker 1: smart happens. Hi Am Marshall Brain with today's question, why

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Speaker 1: do feet stink? Everybody is familiar with this phenomenon. Most

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Speaker 1: of us have a friend or relative who can clear

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Speaker 1: out a room when they kick off their shoes, and

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Speaker 1: even the sweetest smelling person can do a decent job

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Speaker 1: stinking up a pair of shoes by running a few

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Speaker 1: miles in them. So what's going on here? Why do

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Speaker 1: your feet have a stronger odor than the rest of

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Speaker 1: your body does. The main thing that feeds foot smell

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Speaker 1: is sweat. With more than two hundred fifty thousand sweat

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Speaker 1: glands each, your feet are among the most perspiring parts

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Speaker 1: of the body. In one day, each foot can produce

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Speaker 1: more than a pint of sweat. Sweat is basically just

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Speaker 1: salt and water, though, so it doesn't have a distinctive

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Speaker 1: smell of its own. The smell is actually caused by

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Speaker 1: bacteria on our skin that eats the sweat and excretes

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Speaker 1: waste that has a strong odor itself. It's perfectly normal

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Speaker 1: to have bacteria on your skin, and it doesn't ordinarily

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Speaker 1: produce a noticeable smell, But sweat attracts bacteria and gives

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Speaker 1: them a whole lot to feed on. Of course, we

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Speaker 1: sweat all over. Our hands have a comparable number of

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Speaker 1: sweat glands, for example, and most of the rest of

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Speaker 1: our body doesn't particularly stink, the armpits being a notable exception.

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Speaker 1: So what's the difference with the feet. The answer is

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Speaker 1: our socks and shoes. The sweat that our feet excrete

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Speaker 1: can't easily escape into the air like the sweat our

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Speaker 1: hands excrete. It all collects on our skin and in

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Speaker 1: our socks. The bacteria love this dark, damp feast and

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Speaker 1: have a sort of feeding frenzy. When you take off

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Speaker 1: your shoes, the smell that hits you is all the

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Speaker 1: bacteria excretion that's collected on your feet, eat, and in

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Speaker 1: your socks and shoes. The main reason some people's feet

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Speaker 1: are more precisely some people's socks and shoes smell worse

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Speaker 1: than other people's is that some people sweat more than

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Speaker 1: other people. This is just one of the many variable

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Speaker 1: physiological qualities of human beings. This is also why sometimes

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Speaker 1: your feet smell much worse than at other times. It

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Speaker 1: all has to do with how much you sweat. For

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Speaker 1: more on this and thousands of other topics. Does that

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Speaker 1: how stuff works dot Com and don't forget to check

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