I am 16 years old and I have grey hair at the tips but black at roots. Why is this happening?

I first noticed grey hair when I was 8 years old. Since then, I've always had 5-6 hairs which are black (my natural colour) at the roots but white at the tips and the rest of the length. Even if I remove them, a hair of same type comes up in its place. Why is this happening and how can I stop it? I don't want to colour my hair.I am 16 years old and I have grey hair at the tips but black at roots. Why is this happening?
heya.....hope the folowin things help u.....so its ur generation problem of getting grey hair or u must be having natural shades or u must be using gell on ur hair thus its turning grey - white...........so dye ur hair BLACK and bathe everyday and shampoo twice a week and always apply hair oil to maintain the blackness of ur hair :)I am 16 years old and I have grey hair at the tips but black at roots. Why is this happening?
I have a friend with a very very similar condition in his hair. It's genetics man, there's not much you can do asides from coloring it.
you are growing