Oh yes, it WILL happen to you. Don’t worry it happens to all of us, aging that is. More specifically, gray hairs happen. That’s right our bodies, unlike diamonds, aren’t forever. Hair follicles lose their pigment as we age. There is a family of pigments in our bodies called melanins that contribute to hair and skin coloration. So whether your complexion is Godiva, chocolate brown like Djimon Hounsou, salted caramel like Rosario Dawson (call me), or slow churned vanilla like Olivia Wilde, you have melanin to thank. Oh man, all this talk about race makes me want ice cream.
Hair is like sea coral. Yes, that’s random…try to focus. Much of the underlying structure of a coral is the deposited, calcium carbonate remains of dead cells that harden and accumulate while new cells grow over top of the layers. The structural anatomy of a hair follicle is actually curiously complex but the portion of that follicle that we see protruding from the skin (the hair shaft) is just the deposited remains of dead keratinocytes (keratin containing cells). However, unlike coral, the living cells are underneath. Keratin is the crazy strong protein that gives hair, nails, and skin their structure and durability. That same protein that allows Scarlett Johansson’s golden locks to flutter in the wind are what make a rhino’s horns hard enough to dent the door of a Jeep when the tourists get too close.
Clusters of rapidly dividing keratinocytes at the root of the follicle team up to produce keratin. Cell division and keratin production creates a dense mass of material that builds from the bottom up. Meanwhile, bordering those feisty root cells are melanocytes that pass their melanin granules to the keratin producing cells. So even as the cells die they retain whatever color was passed on.
As we age melanocytes become less active and die off and so more and more hair shafts reach the surface without pigment. So just to be clear, your body doesn’t produce gray hairs. It simply stops producing melanin pigment within the hair follicles. The resulting hair strand is actually colorless.
Now the rate at which our hair loses its color is largely genetic. In know, genetics seem to be the new cop-out answer. It’s like when they use “instinct” to explain why ducks fly south for the winter. However, this time we have to point the finger at inheritance for our sexy, silver sheen.
Stay classy, stay curious, and never stop learning my friends :-)