A person’s hair grows periodically. There is the growing period, the retrogressive period and the resting period. During the growing period, hair grows continuously at the rate of one centimeter a month, generally speaking. Probably, 85% to 90% of the hair belongs to that of the growing period. Hair in the resting period accounts for about 10% to 14% of the total amount of hair, while that of the retrogressive period accounts for 1%. Hair generally can grow for three years in the growing period, while the resting period lasts about three months, and the retrogressive period is about three weeks long. Therefore, it is normal to lose 50 to 100 pieces of hair a day. In normal conditions a great part of this amount of hair loss, namely 50 to 100 pieces of hair a day, comes from hair in the retrogressive period.I think you are interested in the male-pattern baldness. The first factor that needs to be taken into consideration in this connection is certainly age. A boy of 16 or 17 has, with very few exceptions, luxuriant hair, which is hard to pull off even with considerable force. An aged man generally has scanty hair, though he may not be considered as bald. Androgen and hereditary factors have to be taken into account anyhow. They may be the cause of the male-sex alopecia. But the hair loss is not incurable now. A few decades ago, extensive alopecia areata was formidable because it might be complicated by cataracts. Now, with the marvelous progress made in eye surgery, this complication of alopecia areata need not be feared at all.hair loss treatmentRelated articles:
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