Learn about hair - how it grows, causes of hair loss and types of hair loss.
If you are experiencing thinning hair, you are not alone. Hair loss affects more than 40 million men and 20 million women in the United States. Until recently, there have been no completely effective treatments for thinning and balding areas of the scalp.
However, there are now surgical procedures and medication options available that can not only slow the hair loss process but actually replace lost hair.
The Growth of Hair
Each hair follicle is genetically programmed before birth to either become sensitive to the male hormones that begin to appear during puberty – causing the follicle to eventually shrink and die – or to not become sensitive and continue growing throughout life.
Every single hair on the scalp grows for two to six years, remains for a time, and then falls out. In fact, every day one loses 50 to 150 hairs. When a hair falls out, a new hair begins growing in its place. Sometimes, testosterone affects this normal growth cycle. Hair follicles, the tiny cup-shaped structures from which hairs grow, start to shrink. In men, this only happens on the front and top of the scalp since the back and sides are programmed to grow for life. In women, hair loss is spread out over the scalp while retaining the natural hairline in many cases.
As the follicles shrink, the resulting hair is thin and sparse. Eventually the follicles shrink to the extent that new hair cannot grow. The result is male or female pattern baldness.
Causes of Hair Loss
Hair loss usually is genetic. If your parents had thinning hair, you have a 95 percent likelihood of experiencing thinning hair or baldness. Certain medications or medical conditions may also cause hair loss.
Although the exact causes are unknown, heredity, hormones and age are contributing factors for the most common type of hair loss, called male pattern and female pattern baldness. In males, this form of hair loss is influenced by sex hormones called androgens, principally testosterone.
Androgens also are present at low levels in women, making them susceptible to female pattern baldness. Contrary to the popular belief that baldness is inherited from the maternal side of the family, it is believed the condition depends on genes contributed by both parents.
Other Causes of Hair Loss
Hair loss also may be caused by a variety of factors including medications, cancer treatment drugs, childbirth, birth control pills, stress, nutritional deficiencies or infections. Contact your physician for diagnosis and treatment.
Types of Hair Loss
Androgenetic alopecia - This is the most common type of hair loss in both men and women and is more commonly referred to as male pattern or female pattern baldness.
In men, the hair usually thins out first in the front of the scalp and moves progressively to the back and top of the head, creating the appearance of a thin or bald spot on the crown of the head.
In women, there typically is a more diffused thinning of hair throughout the scalp. Women rarely develop bald patches.
There is no cure for hair loss caused by androgenetic alopecia, although treatments are available.
Alopecia areata - Alopecia areata is an autoimmune disease, in which the immune system mistakenly attacks the hair follicles. This can lead to hair loss on the scalp and elsewhere. Typically the hair loss involves totally smooth, round patches about the size of a coin or larger. This disease may affect children, women or men of any age.
There is no cure for hair loss caused by alopecia areata, nor approved medications specifically targeted to cure this disease. The condition can be managed by certain medications or it is possible that the hair may start to re-grow on its own. Contact your physician for diagnosis and treatment.