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  • Just another fun part of getting older as people age many of them start to lose their hair. Why? turns out

  • It's complicated otherwise

  • we would have fixed it by now because it's basically the holy grail of beauty.

  • But lots of different factors affect whether or not you end up with a shiny bald head

  • But mainly it has to do with two things.

  • Hormones and genetics. Hormones are involved because they affect how your hair grows more specifically, you can blame

  • Testosterone because balding happens when hair follicles turn it into Dihydrotestosterone, or DHT.

  • Scientists don't know exactly why, but

  • DHT makes certain hair follicles start to shrink as they get smaller, the hair gets thinner and

  • Eventually the follicle stops producing hair entirely

  • Males typically have plenty of testosterone which explains why balding affects biosex males more than females.

  • In what's known as male pattern baldness.

  • Hair loss starts at the temples in the top of the forehead and at the top of the scalp.

  • Eventually the receding hairline meets the growing bald patch but biosex females produce testosterone, too.

  • Just a lot less of it, and they make enough estrogen to mask its effects.

  • After menopause, Estrogen production slows,

  • but they're still producing about the same amount of testosterone, so that's when the hair starts to get thinner.

  • With female pattern baldness it's more of an evenly distributed thinning of the hair across the scalp without much of a receding hairline.

  • So how do you figure out whether hair loss is in your future?

  • Well, that is more complicated,

  • and there's a lot that we still don't know.

  • Mainly it seems to be tied to genetics and researchers have pinpointed a few different genes

  • that might be involved.

  • Some of these genes are on the x chromosome which explains

  • why males are so much more likely to go bald than females.

  • Males get only one x

  • chromosome so whatever version of the gene they inherit on that chromosome is going to be expressed.

  • Females on the other hand have two x chromosome

  • So there's more of a chance that they'll inherit a non balding version of a gene from one of their parents.

  • Studies have shown that there are other genes on non x chromosomes involved too, like one genetic variant on Chromosome 20 which made males

  • 7x more likely to go bald but for some reason doesn't seem to influence whether females experience hair loss.

  • So there are a lot of different pieces to this balding puzzle,

  • which is why we haven't figured it out yet.

  • But if you don't like the new look, there are some drugs that can help .Finasteride for instance works by blocking production of DHT and

  • Minoxidil increases blood flow to hair follicles and widens them, helping hair grow.

  • Of course you could also just embrace your newfound

  • resemblance to Jon Luc Picard it did pretty well for himself.

  • Thanks for Patreon Patron Dafur for asking us this question.

  • And thank you to all of our patrons who keep these answers coming.If you'd like to submit a question to be answered you can

  • go to patreon.com/scishow and don't forget to go to

  • youtube.com/scishow and subscribe.

Just another fun part of getting older as people age many of them start to lose their hair. Why? turns out

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