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Author Topic: Why Does Hair Turn Grey/Gray ?  (Read 11084 times)

Offline neilep

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Why Does Hair Turn Grey/Gray ?
« on: 05/05/2007 19:51:10 »
Dearest peeps with luffley Hair,

In My fam we all started going grey/gray very early.

Why does hair turn gray....why ?...and why does it have to turn gray anyway ?



 

paul.fr

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Why Does Hair Turn Grey/Gray ?
« Reply #1 on: 06/05/2007 08:25:54 »
well, i was going to answer this but i found a much metter explination that i was going to give:

Dr. Desmond Tobin, professor of cell biology from the University of Bradford in England, suggests that the hair follicle has a “melanogentic clock” which slows down or stops melanocyte activity, thus decreasing the pigment our hair receives. This occurs just before the hair is preparing to fall out or shed, so the roots always look pale.

Moreover, Dr. Tobin suggests that hair turns gray because of age and genetics, in that genes regulate the exhaustion of the pigmentary potential of each individual hair follicle. This occurs at different rates in different hair follicles. For some people it occurs rapidly, while in others it occurs slowly over several decades.

In a February 2005 Science article (Nishimura, et al.) Harvard scientists proposed that a failure of melanocyte stem cells (MSC) to maintain the production of melanocytes could cause the graying of hair. This failure of MSC maintenance may result in the breakdown of signals that produce hair color.

There are other factors that can change the pigmentation of hair, making it lighter or darker. Scientists have divided them by intrinsic (internal) and extrinsic (external) factors:

Intrinsic factors:

Genetic defects
Hormones
Body distribution
Age
 Extrinsic factors:

Climate
Pollutants
Toxins
Chemical exposure
 

Hair-raising facts:

An average scalp has 100,000-150,000 hairs.


Hair is so strong that each hair can withstand the strain of 100 grams (3.5 ounces). An average head of hair could hold 10-15 tons if only the scalp was strong enough!


Human hair grows autonomously, that is each hair is on its own individual cycle. If all our hair were on the same cycle, we would molt!


Hair has the highest rate of mitosis (cell division). An average hair grows 0.3 mm a day and 1 cm per month.
 

Offline neilep

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Why Does Hair Turn Grey/Gray ?
« Reply #2 on: 06/05/2007 17:16:26 »
EXCELLENT POST PAUL..THANK YOU !!


It would still be nice to know why hair has to turn grey anyway though !...but your post is extremely informative..THANK YOU very much indeed!!
 

Offline Seany

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Why Does Hair Turn Grey/Gray ?
« Reply #3 on: 06/05/2007 17:30:02 »
Hmm.. I always thought that the colour cells or something die out.. But I'm probably wrong with that. ;D
 

Offline Karen W.

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Why Does Hair Turn Grey/Gray ?
« Reply #4 on: 06/05/2007 17:39:29 »
I thought and I may be wrong that something happens and the hair follicle dies, The hair still grows, but it turns gray... We all started getting gray at about 19 or twenty some of us sooner in my mothers side of the family.  I have a friend who got a really bad high fever when she was twentyfour. within days she was noticing weird hair color growing from this spot on her head about twice the size of a quarter. within weeks she had a huge gray patch emerging from her head. Now this was no ordinary fever, she was very sick with this fever for several weeks and in the hospital, they worked trying to keep her fever down, I cannot remember what she had.. it wasn't good.. any way, The doctor told her the fever had caused this and it would never be normal there again, she had chestnut brown hair and a two inch in diameter gray almost white patch of hair that grew off the Left front side of her hair as if it were dyed there! LOL after we all got used to it we all loved it. It was a cool phenomenon!
 

Offline that mad man

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Why Does Hair Turn Grey/Gray ?
« Reply #5 on: 06/05/2007 18:22:38 »
I don't understand how but I have had hair that has gone grey and then started to go black again all on the same strand.

Bee


 

Offline ukmicky

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Why Does Hair Turn Grey/Gray ?
« Reply #6 on: 06/05/2007 18:39:28 »
T
I don't understand how but I have had hair that has gone grey and then started to go black again all on the same strand.

Bee



That tends to happen when the melanin producting cell beings to die which is not always a quick thing. You will also find that grey hair grows stronger and faster than coloured hair and i was once told it was because the energy available to each hair used to be shared between colour and growth and once the colour side goes it then all becomes available for growth.

Not sure if the last part is true though.
 

Offline neilep

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Why Does Hair Turn Grey/Gray ?
« Reply #7 on: 06/05/2007 19:28:42 »
I don't understand how but I have had hair that has gone grey and then started to go black again all on the same strand.

Bee





This is cool...I want two tone hair !!
 

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Why Does Hair Turn Grey/Gray ?
« Reply #7 on: 06/05/2007 19:28:42 »

 

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