The product has been discontinued
The product has been discontinued. res that seem to pop up out of nowhere well that’s just a normal part of life as our bodies age and change so the next time you find a new hair in a place you didn’t expect it just remember it’s been there all along
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It’s happened to all of us: you’re going about your day, checking yourself out in the mirror, and all of a sudden you see a dark, thick hair growing where it never used to. Now, to be clear, you always had a hair growing there; it just didn’t look like that before. And scientists do know why some hairs transform from peach fuzz into something a little more luscious, but that doesn’t make it any less random.
While some parts of your body like your head and your armpits really call attention to their hairy adornment, pretty much all of your body is covered in hair. In fact, you have the same number of hairs packed into each square centimeter of skin as a chimp; it just doesn’t look like it because you’ve generally got two distinct kinds of hair. The light and thin peach fuzz found in places like your arms and back is what those in the biz call vellus hair, and the long, dark, and handsome more associated with the top of your head and your unmentionables are terminal hairs.
That’s not to say that everyone’s back looks like a baby’s butt; we humans vary in how dark the hair on different parts of our bodies can get, so consider those examples as places that are lighter and darker than the hair on other parts of your body and we love and appreciate both types of hair for their unique contributions to our survival.
First, the top of your head needs protection from the sun, specifically the ultraviolet radiation that it sends towards the Earth, and thicker, darker terminal hairs can absorb more UV rays, blocking them from getting to the skin below. But instead of getting that UV protection all over our bodies, we have vellus hairs to keep us from overheating.
When humans overheat, we sweat, and humans are particularly sweaty animals; we have significantly more sweat glands than other primates, but if we had just as many terminal hairs, they’d cover up those glands, and the sweat they make couldn’t wick away from our bodies to cool us down.
So in some parts of your body, it’s really helpful to have those barely-there vellus hairs, but in other, super sweaty parts like your armpits and butt crack, you’ve got a bunch of terminal hairs stuck where the sun don’t shine, so they don’t really seem poised to protect you from a bunch of UV rays. So instead, some research suggests they may help you spread your musk and attract a partner. That might explain why why these terminal hairs tend to appear when your body goes through puberty.
But regardless of why your armpit hairs become voluminous at puberty, it’s clear that that stage of life is when lots of dark hairs emerge and I know it seems like they appear out of nowhere, but it turns out they were there all along. Those suddenly dark hairs used to be vellus hairs, and they were nudged into the transformation of a lifetime by your hormones, specifically your androgens.
When androgens bind to a vellus hair follicle, they can activate a gene with the catchy name of HHA7, and once that gene gets turned on, the vellus hair follicle starts working with more of the protein keratin, and the hair grows longer, thicker, and darker. Now, not every vellus hair cell in your body has this HHA7 gene turned on, but they are in some unexpected places like your scalp, so they’re not just in the places that are famous for getting super hairy after puberty.
On top of that, some of these cells rocking HHA7 also have more receptors, which makes it easier for androgens to swoop in and order the switch, so some cells, no matter where they are on your body, are predisposed to a darker, thicker fate.
As humans move through various life stages like puberty, pregnancy, and menopause, the body makes different amounts of androgens than it did before, and any one of these could trigger the transformation of whole patches of vellus hairs into terminal ones.
But what about those single terminal hairs that seem to pop up out of nowhere? Well, that’s just a normal part of life as our bodies age and change.