|
By Melissa Tennen, HealthAtoZ contributing writer
A wiry strand here and there when you were in your 30s didn't seem like too big a deal. You just plucked them out. Now it seems your crowning glory is gray.
How did that happen?
Eventually your body stops producing a substance called melanin, which gives your hair its color - red, brown, blonde and black. This is the same substance that determines the color of our skin. The more you have of it, the darker your skin and hair.
Each strand of hair grows out of follicles, which are basically tubes of tissue. These follicles have a certain number of cells filled with melanin - melanocytes. These live at the base of hair follicles.
As we age, our bodies make less and less melanin, causing hair to start growing in gray. The hair still has some melanin in it, just not as much. Eventually, your hair will be all white because your body has completely stopped making melanin. Even your body hair turns white.
A single strand of hair does not suddenly become gray. Hair has a life cycle. One strand takes several years to grow. It then enters a rest period for a few months before falling out. This happens throughout life - whether you have gray hair or not. When the hair follicle makes a new strand of hair, there may be less melanin. This causes the hair to grow in gray.
Your hair does not turn gray overnight. In fact, it can take 10 years or longer for all your hair to turn gray. Although it's possible to get gray hair in your teen years, most people start seeing gray hair between ages 35 and 50. When you get your gray hair depends on when your parents started turning gray.
It is not clear why the body stops making melanin. There is no evidence that shows stress or trauma turns your hair gray. Some medical conditions can turn your hair gray:
- Not enough vitamin B12 in your diet.
- Thyroid disease (the thyroid is a gland that regulates how your body uses energy).
- Tuberous sclerosis (a rare condition causing harmless tumors in the body)
- Vitiligo (a disease where melanocytes are lost or destroyed)
Men tend to turn gray earlier than women and Caucasians tend to develop gray hair sooner than African Americans or Asians. No one is sure why. Smokers tend to go gray earlier. Gray hair usually starts at the temples, then the top of the head before spreading out.
No matter how you look at it, gray hair is a normal part of aging.
Return to the previous page
|
