Hair 101 — Section 2

Welcome back for the second half of your Hair 101 course. Hopefully you’ve been taking copious notes. In Section 1 of Hair 101, we covered just what makes up a human hair (hint, keratin) and how the 5 million or so hairs on our heads and bodies grow.

In Section 2, let’s get into some other stuff about hair, and then get to the good stuff — how to destroy the hair follicles that you no longer want to produce hairs.

Where’s the hair?

Humans grow hair everywhere on the body except the soles of our feet, the lips, the palms of our hands, some external genital areas, the navel, scar tissue, and, apart from the eyelashes, the eyelids.

The body has different types of hair, including vellus hair and androgenic hair. These have different cellular constructions, giving different areas of hair different characteristics. Hair in most places keeps us warm and provides physical protection. Our longest hairs, fortunately, are found on the scalp. They can grow up to 30 inches, despite what Rapunzel claims.

Although we’ve developed coats and other stuff to keep us warm out in the wilderness, our body hair is there for that reason. It does help to regulate our internal temperature. When the body is too cold, the arrector pili muscles found attached to the hair follicles stand up, causing the hair in these follicles to do the same. These hairs then form a heat-trapping layer above the epidermis. The opposite action occurs when the body is too warm; the arrector muscles make the hair lie flat on the skin, which allows heat to leave.

Where did it go?

Despite having 5 million or so hairs, we’re still basically one of the few hairless mammals, at least compared to the others like foxes or chimpanzees. There are theories as to why we lost our hair.

One says it is due to the loss of functionality in the pseudogene KRTHAP1 (which helps produce keratin, which is what makes up hair) in the human lineage about 240,000 years ago.

On the evolutionary side, the theory is that we devised new hunting techniques that led to higher protein intake than when we were hairier. Our bodies and brains became larger. Another theory says that when hunting in the equator, our bodies needed to rapidly expel heat. This made humans evolve the ability to sweat, which is facilitated by the loss of body hair.

Not hairless enough

Ah, but we’re not hairless enough for most of us. That’s why we shave, pluck, wax, and use nasty depilatory creams to get rid of the hair we don’t want. That process is so Sisyphusian, however. You remember him, right? In Greek mythology he was punished for cheating death by having to roll a boulder up a hillside all day, only for it to roll down again at night, requiring him do it all over again the next day…for eternity.

Fortunately, there is a better, more evolved way to get rid of unwanted hair — applying laser energy to the hair shaft. That laser light energy converts to heat and travels down the hair shaft into the hair follicle. There the heat destroys or damages the follicle, and it can no longer grow new hair. Ah, the wonders of permanent laser hair removal.

That’s our thing at Romeo & Juliette Laser Hair Removal, New York’s most evolved permanent hair removal specialists. Why not call us today at (212) 750-2000 and set up a consultation so we can help you get rid of some of those unwanted hairs.

Until then, thanks for passing Hair 101 in these two blogs of September. Now go out and impress your friends with your newfound knowledge.

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