Scalp hair grows about one-and-half inch a month. Losing 50-to-100 hairs per day is no cause for alarm. Shaving of the scalp is not an answer to your problem. Hereditary balding or thinning is the most common cause of hair loss (could be your case). Other causes are illnesses, thyroid disease, medications etc. Dandruff rarely causes hair fall but its severe form Seborheic dermatitis can cause reversible hair loss. Minoxidil (2% or 5%) lotion and finesteride (1 mg) are the common medications known to increase the hair growth.