Here's a question that people ask the internet all the time - seems natural enough - why
do feet smell?
But what's a little peculiar about this question is how people tend to ask it in really specific,
and frankly kinda gross ways, usually in reference to food.
Like "why do my feet smell like popcorn?
Or why do my feet smell like chips?
Or like Doritos?"
Now you'd think that we'd be pleased that our bodies have the ability to create the
smells of tasty snack foods; really, I think the question is why do Doritos smell like
stinky feet?
But, for most of us, when that smell comes from a part of our body and not from a freshly-opened
bag of Bugles, it can be a little off-putting.
Foot odor comes from sweat, and your feet and hands have the highest concentration of
sweat glands of any part of your body.
That's why they get so sweaty when you have gloves or shoes on.
But your sweat doesn't have any inherent odor of its own; it only starts to stink when it
comes into contact with the bacteria on your skin, which happen to think that your bodily
secretions are totally delicious.
Like we've talked about before, you are simply covered in germs.
There are more micro-organisms in and on your body than there are cells in your body.
And certain species of germs, like Staphylococcus epidermidis and Bacillus subtilis, feast on
the nutrients in your sweat - particularly the essential amino acid known as leucine.
The thing is, when these bacteria metabolize leucine, they create a compound called isovaleric
acid, otherwise known as this.
And yeah, not exactly a household name, but you would recognize it by its signature smell,
which has been described variously as pungent, oily, and cheesy, just like Doritos.
It's because of this smell that isovaleric acid is actually used as a flavor additive
in a lot of foods, and it is thought to give certain cheeses their distinctive taste and
odor.
So yes, when you feel like your feet are manufacturing the secret ingredient in nacho cheese corn
chips, you are.
As for how to get rid of the smell, tests have shown people who exercise regularly tend
to lose fewer amino acids in their sweat, and therefore smell less than people who don't.
So put down that snack bag, get out there, and do some stuff.
I'm not going to.
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