Losing Your Hair?

Why do we lose our hair?

More than half of men and women in the United States experience hair loss. It is very common and not just relegated to humans, as even chimpanzees lose their hair.

There are four forms of hair loss:

• Androgenic alopecia -- the most common type, also called male pattern baldness.

• Traumatic alopecia -- from hair being torn out.

• Drug-induced alopecia -- caused by one of many medications.

• Alopecia areata -- Patchy, usually reversible.

Many factors cause hair loss, varying from genetic to hormonal and baldness that genetically can come from both sides of the family. Testosterone, specifically the hormone dihydrotestosterone, or DHT, plays a tremendous role. Hair follicle receptors are sensitive to DHT, so they start the process of hair loss.

DHT is transformed into its present state by an enzyme called 5-alpha reductase. This enzyme helps in creating DHT because it links itself to testosterone molecules, which are then transformed into DHT as we know it today. DHT aids in male and female hair loss by attacking the hair follicles during their regrowth phase. Also, while we grow hair over a lifetime, we do not generate new hair follicles, which finish forming when a fetus is 22 weeks old. At that stage, there are about 5 million follicles on the body, with 100,000 follicles residing on the scalp, the most a human will ever have. The density of our scalp hair will reduce as we grow from childhood to adulthood for another reason -- as we grow, our scalps expand.

Source: WebMD; eMedicineHealth