Why do white hair turn into grey hiar ?

hi, my friend's mother white hair turn into grey hiar now,could you tell me why ? what kind of illness?she is 60 year old now.

Why do white hair turn into grey hiar ?

Hair gets its colour from a chemical called melanin, which is pumped in by cells at the base of the hair follicle. As your hair turn grey, these cells at the base stop making melanin. So some hairs will be their normal colour, but some (the ones without melanin) will be completely white. So here's a great truth - there's no such colour as grey hair. Grey hair is dark hairs, with the newer white hairs mixed in.

Why do white hair turn into grey hiar ?

It's not illness... It's aging.

All older women at that age of 60 has their hair turn gray.