According to the American Academy of Dermatology there are 50 million men and 30 million women in the United States alone suffering from hair loss. Physicians divide hair loss, or balding, into scarring or non-scarring alopecia. Scarring alopecia includes a variety of diseases that cause patchy hair loss due to internal disease or trauma, or certain chemical agents. Stress can also cause hair thinning in a generalized way all over the head.
Only one type of hair loss with give a distinctive pattern of hair loss in men and women. This is called male and female pattern baldness. This is the most common for of hair loss for both men and women. It is caused by the effects of DHT (dihydrotestosterone) on the hair follicle in both men and women. Men and even women have a certain amount of male hormones in their bodies which is broken down by the enzyme 5 alpha-reductase to DHT.
In females, the effects of DHT on the hair follicles gradually, over many years, results in a slow thinning of the hair on the top of the head. This gives us the Ludwig patterns 1,2, and 3.
In the case of males, distinct and progressive pattern baldness usually starts in the 20’s, 30’s, and 40’s and continues briskly for eight to fifteen years. After that it slows down but continues at a slow, progressive course for life. In both male and female pattern baldness, the effects of DHT on the hair follicles cause a gradual miniaturization of the hairs produced by the follicles until they eventually stop growing and fall out. This is why a person’s hair will feel finer for several years before actual baldness occurs.