The scalp has around 100,000 hair follicles. It is considered normal to lose about 100 hairs on a daily basis. The growth phase, also called the anagen phase, lasts an average of three to five years. Once the cycle is complete, it restarts, and a new strand of hair grows. For some people, as they reach a certain age or have specific medical issues, the hair growth cycle doesn’t start over, and they begin to see the effects of hair loss.