Hello..... Hormonal changes and imbalances can cause temporary hair loss.....Scalp infections. Infections, such as ringworm, can invade the hair and skin of your scalp, leading to scaly patches and hair loss. Once infections are treated, hair generally grows back..  Intake of too much vitamin A may cause hair loss as well. The most common cause of hair loss is a hereditary condition, in this case both hair thinning and hair fall can occur ... Consult dermatologist .