[Moontanman]

I'd like to know why, I have been told that i have enough hair to cover several heads. My hair is not only very thick it is also very course. there is hardly any room for scalp, brushing my hair is a real problem. I have to use very strong brushes and or thick flexible plastic combs with wide spread teeth. Afro combs are the only real answer (yes I do have some African ancestors but mostly native American with some Scot and Irish thrown in for fun ) My hair started to go gray when I was in my late twenties now at 53 it's white. I see most people with white hair have thin hair. Mine is thick and course as ever maybe more so now. What causes it to be this way? It was dark brown almost black to start with. I wear my hair long down my back Every controlling bald butt head I know wants me to cut it so bad it's almost funny.

[Boerseun]

I read an interesting article about hair on Wiki when searching about info on hair for this thread.

Turns out that hair acts like optic fibre, and transfers UV right from the hair surface to the scalp, increasing the ease of Vitamin D production. Interestingly, Africans, being exposed to more UV, have densely curled hair, and it's been shown that UV can't travel down the hairshaft of tight curls because of the wavelength of UV light. Harsh UV conditions also accounts for their dark skins. Sounds a bit far-fetched, but makes perfect sense if you think about it. Europeans, having lived in much colder climes than their African ancestors, have wrapped most of their bodies in animal skins, exposing only their faces and hair to the elements. This might also account for the lightening (and straightness) of northern European hair, blonde, straight hair having less resistance to UV passing through it.

Could this plug in somewhere to greying hair? Could it be that the older a person gets, something happens in the dermis that might make it harder to produce vitamin D from sunlight, so that more UV is required? Which means that as a person ages, the increasing greying of the scalp hair is simply a response to a lack of UV?

Could it be that melanin added to the hair in the first place is simply as a sunblock, controlling the amount of UV from travelling up the shaft? Pure keratin with no melanin added, is, after all, simply a grey hair - the melanin is clearly optional. And the ability to add melanin at the cellular level can then surely be turned on or off, in response to the environment?