why does hair turn grey in older mamals ?
469294
Hair is an interesting biological structure. What we usually think of as 'hair' is really just the part we see... that's the hair shaft, which contains pigment (a chemical that gives color to things). There is also a hair follicle, which is a multi-cellular structure inside the skin of our scalp that creates the hair strand (making it grow), and also is responsible for the pigmentation. Some of the cells in the follicle make the chemical melanin, which is a skin and hair pigment in many species on our planet. \n\nHair turns grey when the pigment cells in the hair follicle stop making melanin. When this happens due to aging, it's mostly under the control of the genes we inherit. Long periods of constant stress may also contribute, but a big shock won't turn hair grey overnight.
142612
your hair turns to a diffrent color than you was born with
598740
I think I've heard that stress doesn't cause it, but I have to wonder. I've seen too many get grey hair in a hurry, after a stressful event.
107212
The melanocytes aren't producing melanin to color the hair.  This could be due to nutrition, or they could just be turning off.
252092
Yes. I have gone through it. People react different to it. It usually happens when people realize that they are not "young" anymore and inside they still feel young, but on the outside they are wrinkling up and truning grey. The outside appearance does not jive with inside feelings.
595304
Male baldness is passed on through your mother.  If your maternal grandfather is bald, then your mothers son will have a higher chance of being bald.
1118943
it may be your hormones changing as you get older things change, my mom went through the same thing and found it just to be stress and aging. she found the best thing that worked was proactive!
467491
The hair below may not be as light as the hair that is atop our heads because the hair on our heads is exposed to the effects of sun. \n\nMy hair is fairly light all over, something you may not know is that when you get older and the hair on your head begins to turn gray your hair "down under" may also turn gray!  \n\nMy great grandmother told me once after it turned gray that all the hair fell out, but I don't know if that was the truth, (I never looked to see) if I live that long I am sure I will find out though! :D\nruthie~
256592
It should tone down a bit after several days.  It's probably just the excess dye in your hair.
598635
Because it has to do with genetics.  If your parents had brown hair then most likely you will have the same color.  If they have blond hair then you may also get blond hair.  It all depends on your genes.
522175
why does your hair look gray?
284011
The only remedy is to colour it and disguise the grey! Suggest highlights n lowlights to keep it looking natural and to avoid very obvious re-growth at the roots...I got my first grey hair at 18..its all down to genetics but can look fantastic too!
581410
In general, most things that happen that signify age, from infanthood to old age, are genetically regulated development processes.  At some point, in those who carry the genetic predisposition, certain proteins will start to be expressed, and others will be decreased-Though it's unclear the exact genetic cause of gray hair, this is likely the cause.  Support for this hypothesis comes from the fact that not all people turn gray, that it has no clear relationship with health or longevity, and that some people turn gray quite young- All these point to a genetically controlled developmental change.
516003
hi your mum should seek medical advice ,normaly this happens first as your body is changing  your mum has along way to go through menopause as i started at the early stage of 38 .i went through the same problems im now 60 go along with her to your family doctor for suport  but every thing will be ok its normal
898826
Most of the answers here are incorrect.  You can turn grey from illness but it's generally just genetic.  In my family we all start greying at 16 and have quite a bit by the time we're in our early 20's.\n\nThe darker your hair the more the grey shows so you may not even notice grey hair on a blonde.\n\nThere are LOTS of young people with grey hair but 19 is pretty young to be very grey.  I do know one guy who was snow white by his early 30's.
443183
Age?  Personally, mine has changed from light brown to dark brown after having children due to the body chemistry changes.
250728
Personally, I wouldn't worry about it. Don't, I repeat, DO NOT dye your hair! If it's healthy enough to have that long, dying it will ruin it, as you said. And don't cut it! Take pride in your hair! You've obviously cared for it to have it that long, so don't ruin it now. And you are not an "OLD gal" so don't even THINK it! If you are so terribly concerned about those three grey hairs, pull them out. You will go grey eventually, everyone does, but don't worry about it. Your hair is healthy, so it should grey gracefully and beautifully!