Testosterone is needed in men to maintain normal bone and muscle health, reproductive and sexual function and good mental health and wellbeing.  This type of hair loss is a result of the hair follicles becoming sensitive to testosterone.  In some men, usually due to inherited genetics, the hair follicles become more sensitized resulting in the hair follicles become miniaturised with the subsequent failure of hair growth.

There are other types of hair loss that are not related to testosterone and genetics.  They include:

• Involutional Alopecia: this is the age-related thinning of hair that occurs
• Alopecia Areata: this hair loss can be patchy or complete. It is related to an autoimmune response of the body that attacks hair on the body.
• Anagen Effluvium: this is loss of hair related to chemicals, often chemotherapy or radiotherapy.   Usually most of the hair grows back after about 3 months
• Telogen Effluvium: this is hair loss related to hair not progressing past the resting phase of growth. It often occurs post stresses such as surgery, illness or other major stresses.
• Traction Alopecia: this hair loss is result of constant tension being placed on hair, like this who have tight hair styles.