Mind & Body

Sweat Is Not Detoxifying

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Doesn't it feel good to sweat? To feel your muscles warm up, to feel your heart pump, to feel the toxins escape through your pores ... well, everything except that last part. It turns out that, contrary to popular belief, sweat really isn't detoxifying. The real detox happens in completely different organs. Still, we love to sweat all the same.

Sweat It Out

Saunas, hot yoga studios, and sweat lodges all swear by the detoxifying effects of sweating. And it seems reasonable: Something smelly is coming out of your pores, which means there's less smelly stuff inside of you. Right?

In truth, hardly any harmful chemicals come out in your sweat. Sweat is mostly water, plus a certain concentration of sodium, chloride, and potassium, and sometimes proteins and fatty acids. It does include some "toxins," but only trace amounts, and those are dwarfed by the quantities that your liver and kidneys constantly flush out of your body.

"Most of the 'toxins' that concern people include pesticides, residue from plastics, or from air pollution," dermatologist Tsippora Shainhouse told Vice. "These tend to be fat-soluble, and do not dissolve well in water, so they will not be removed from the body in any significant quantity, given that sweat is 99 percent water."

One Big Stinky Myth

But what about the smell? The stink of sweat isn't from toxins, but from the chemistry of your own skin. You have two types of sweat glands: eccrine glands and apocrine glands. Eccrine glands are located all over your body, and the sweat they produce is there to cool you down when you're hot. That sweat is usually odorless, but it can take on a funky smell when it's broken down by bacteria on your skin or if you've been eating particularly pungent foods like garlic or cabbage. Sweating after a night of drinking can also douse your eccrine-gland sweat with diacetic acid, which smells like vinegar — though again, you're just sweating out the smell, not the alcohol or any other "toxins."

Your apocrine glands lead to even funkier sweat. These glands are located in the spots known for stinky smells, like the groin and armpits, and they're responsible for the telltale scent of stress sweat. The sweat they produce is milky and odorless until, again, the bacteria on your skin start chowing down and producing a bouquet of B.O.

To reiterate: Both types of sweat start out odorless, for the most part. They only get smelly when they interact with the bacteria on your skin, and any smell they do start out with is due to compounds your body has already broken down and was getting rid of anyway. Sweat is almost entirely water, and that water contains hardly anything you could consider a toxin.

On the contrary, attempting to "detox" by sweating it out can actually do more harm than good. If you don't replace that sweat by drinking enough water, you'll get dehydrated, which is the perfect way to stress your kidneys and keep them from doing their job — you know, the job of detoxifying you. That's not to say sweating is bad. It's a great way to cool off, as long as you follow it up with a refreshing swig of water.

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Written by Ashley Hamer June 26, 2019

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