Hair Loss for Men

Hair Loss for Men

Hair loss for men can feel like an embarrassing issue.  However, there are many men who experience hair loss.

Hair loss for men is also known as male pattern hair loss, male pattern baldness and alopecia.

The most common cause of male pattern hair loss is androgenic alopecia.

Basically, androgenic alopecia is hair loss caused by high levels of the hormone testosterone.  Actually, it is the most active and potent form of testosterone, dihydrotestosterone, that causes male pattern hair loss.

Testosterone has a lower affinity for binding to the androgen receptor than dihydrotestosterone.

Androgenic alopecia affects approximately 50% of men by the time they turn 50 years old.

Hair grows out of structures located in our skin called follicles.  The growth of hair from our follicles is actually rather complex.  It has been found that hormones play significant role in controlling hair growth.

In fact, hormones are known to influence the distribution of hair, the type of hair growth, the growth rate of hair, and the natural cycle of follicles.  Androgens are the hormones which exert the greatest influence on hair and hair growth.

Testosterone is metabolized to dihydrotestosterone by an enzyme called 5-alpha-reductase or 5a-reductase.  You can probably see that if 5a-reductase is needed to convert testosterone to dihydrotestosterone, it is going to play an important role in male pattern baldness.

There are two different types of 5a-reductase. Type 1 is is found in scalp skin, sebaceous glands, chest/back skin, the liver, adrenal
gland, and the kidneys. Type 2 is found specifically in the hair follicle.

All hair growth on the body, other than the hair on the scalp, requires androgens to stimulate its growth.  For men who are genetically predisposed, androgens can have an adverse effect on scalp hair growth.  In these predisposed men, androgens actually cause a thinning of the hair and a reduced growth phase specifically for the scalp hair follicles located in the front and vertex of the scalp.

Men with male pattern hair loss have been shown to have increased 5a-reductase activity in their hair follicles.  This means increased dihydroxytestosterone levels at the hair follicle.

Finasteride, is a drug which is a selective inhibitor of Type 1 5a-reductase.  By blocking 5a-reductase, finasteride blocks the conversion of testosterone to dihydroxytestosterone.

Due to this mechanism of action finasteride is used as a treatment to stop male pattern baldness.

To learn more about other embarrassing health issues visit our Conditions page.