So, it’s summer (at least where I’m from), and everyday when we go out, we get all hot and sweaty from the sun. But why is that? What is the purpose of sweating all the time, making us nasty and wanting to shower?
It turns out that we have sweat glands to cool ourselves when it gets hot. If we didn’t sweat or have sweat glands, we wouldn’t have any way to control how our body temperature changes, and we would easily develop heatstroke from overheating of the body. When our body temperature gets high enough (through exercising or outside heat), the hypothalamus in our brain (the part of our brain that controls our hunger and our body rhythms) tells our sweat glands to start producing sweat.
There are two types of sweat glands: apocrine and eccrine.
Image SourcE: Umkehrer
Apocrine sweat glands are deeper in the skin and secrete more sweat than eccrine glands. They are located mainly in the armpit and in the eyelids (which is why when you exercise, you get really sweaty armpits). They actually don’t function until you hit puberty, upon which hormonal changes start to happen, and they become active (which is why sweaty armpits weren’t a problem when you were a kid).
Apocrine glands are special because the “sweat” they produce isn’t what we typically consider “sweat”; rather, it’s actually a substance that helps the bacteria in our skin flourish to keep our skin nice and healthy and also gives our sweat that nasty stickiness and odor.
Eccrine sweat glands are ten times smaller than apocrine sweat glands, and are located much shallower in the skin. They are everywhere except the lips and the genitals, and they produce what we typically consider sweat (i.e. the salty liquid that comes out when you exercise). The eccrine sweat glands function to maintain the skin’s acid mantle, which is basically the chemical force field that keeps bacteria from infecting your skin, and to get rid of extra water and electrolytes.
I bet you’re probably sweating just from reading all that, but at least you now know how your sweat glands work!
