Everyone loses about 100 hairs per day. That’s not much if you consider the average scalp has more than 100,000 hairs.
Each hair has a lifespan of about 4.5 years before it falls out and is replaced. However, genetic baldness occurs when the hair doesn’t grow back and not by excessive hair loss.
Partial or complete loss of hair is also called alopecia. As we age, men and women lose their hair thickness and amount. Sudden physical or emotional stress can cause your hair to come out while you shampoo, comb, or run your hands through your hair scalp (called Telogen effluvium) and should decrease over 6-8 months.
Call your doctor if your hair loss occurs with some other medical condition or symptoms. A careful medical history and examination of the hair and scalp are usually enough to diagnose the cause of your hair loss.