What causes hair loss in men?
Men are most often affected by hereditary hair loss: the hair follicles react to DHT, a by-product of the male sex hormone testosterone, with a hypersensitivity.
This hair loss develops rather gradually and results in the typical receding hairline, leading to a characteristic bald pate with just a fringe of hair.
Hair loss as a consequence of illness, malnutrition, or psychological problems is very rare in men.
Stages of alopecia in men
Male hair loss is classified according to the Hamilton-Norwood scale.
This scale describes seven types of genetic hair loss in men. It was developed by Hamilton in 1951 and modified by Norwood in 1975.
- Typ I: No or very minor visible hair loss.
- Typ II: Hair loss at the front and towards the back of the head. A slightly receding hairline.
- Typ III: The hairline is now receding towards the back of the head and is in a form identifiable to observers. A tonsure (circle) may also develop at the back of the head.
- Typ IV: The forehead area becomes balder and the tonsure larger. The two affected areas start to move towards each other.
- Typ V: The areas of pronounced hair loss are now only separated by a narrow border.
- Typ VI: The areas of hair loss merge together.
- Typ VII: The conventional appearance of hair only remains as a fringe of hair (donor area), and a fully bald head has developed.