stinky

[Reiwa]

Why are whole-body deodorants suddenly everywhere?

Different parts of the body make different kinds of sweat — and different kinds of smells
Not all sweat is created equal: Human bodies have two kinds of sweat glands, and their products are not exactly the same.

Apocrine sweat glands are typically concentrated in the places where hair grows during puberty — the armpits, the groin, and the butt. These glands make a waxy substance that certain bacteria love to eat, and it’s the byproducts of that microbial banquet that create the musky aromas most commonly associated with body odor.

“The sweat in our armpits is different — quite different — from the sweat that covers your body,” says Andrew Best, a biological anthropologist who studies sweat at the Massachusetts College of Liberal Arts. That’s because the rest of your body is covered with eccrine sweat glands, whose product is a more watery, salty liquid that’s less appealing to bacteria but does a bang-up job of keeping us cool.

Eccrine sweat is what covers most of our body during exercise. It might occasionally evoke recently ingested food and drink, with particularly piquant notes after a garlic bread binge or a very boozy night. Still, because it’s not well-suited for bacterial consumption, eccrine sweat just doesn’t usually generate the odors that apocrine sweat does.

There is such a thing as dysfunctional sweating: About 10 million Americans produce way more sweat than their body’s temperature-regulating needs, either as a consequence of certain medical conditions or medications, or just because it’s the way they’re wired — a condition called hyperhidrosis. Other, less common medical conditions produce particularly pungent sweat.

But most of the sweat most people produce serves a positive biological function: “Sweating is almost always good,” says Best.