It may be easy to determine the cause of hair loss, or a doctor may need to run tests to determine the root cause.
For men who are experiencing a receding hairline or hair loss that worsens slowly with age, the condition may be a result of male pattern baldness. Male pattern baldness is permanent hair loss type with no cure, but there are several treatments available to help slow hair loss and even regrow hair.
However, it is recommended that men who are suddenly balding with no apparent cause or pattern seek medical attention to determine the cause. These cases of sudden hair loss may be caused by a medical condition, such as alopecia areata, vitamin deficiency or the side effect of a medication. The good news is that these types of hair loss are typically temporary and resolve when the medical condition is treated.
Sources:
American Academy of Dermatology