Hair Loss! The science bit...
It's pretty common to lose
hair when dieting. Here's why...
Each
hair on your head grows for 4-5 years, then falls out. So your
hair is always renewing itself. The long growth stage is called
anagen and the short stopping phase that follows is called
catagen. Then the
hair falls out, which is
telogen. The
hair follicle then goes back into
anagen and makes a long
hair for the next 4-5 yaers.
What happens during weight
loss is
Telogen effluvium. It also happens after any stress to the body. Some of your
hair follicles go into
catagen to conserve body resources. So the hairs stop growing and "rest". Once your body feels safe again, those hairs go back into
anagen - but because there was the pause in the middle, the brand new growing
hair pushes the old
hair out of the follicle. So in reality you have just as much
hair as you did before - and it's probably far healthier
hair. But the new hairs are short
Normally around 10% of your head of
hair is in the
catagen or
telogen phase, in essence resetting itself to prepare for new
hair to grow in. Because you have so much
hair on your head, you don't even notice. During weight
loss that percentage gets higher, but this is only temporary. Your body starts creating new
hair in its normal
cycle once it settles into a healthy weight and those hairs start growing again. Remember that
hair doesn't reach a long state overnight! So all those new, healthy hairs need time to grow out to whatever length of
hair you have chosen.
Usually it takes 6 months for your head of
hair to have grown back out to typical fullness.
Hair grows around 1/2" per month, so at the 6 month mark, the
hair is around 3" long which is enough to seem thick on most heads. Again, it's not that the
hair is MISSING during this intermediate time. It's just that it is brand new and growing from scratch.
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Weight Loss, HairLoss and Low Carb - Low Carb if you want to read the whole article!