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Almost half of my hair are white at age 19. It's a heriditary trait but is there anything I can do to make it grey slower?
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Might be worth a quick look:
http://www.thenakedscientists.com/forum/index.php?topic=9077.0
I started get grey early too.
You just have to make the best of it . . Like this guy did:
Grey slower? You can't change your genetics. Just look at Ancient Hippy's answer because that's all you can do about it.
My hair was white and blonde when i was young now im bald
When I was twenty my hair was snow white. After military service, over the years I had to dye my hair for job interviews.