The most common cause of hair loss in men is Androgenetic alopecia which is also known as male pattern baldness (MPB). Men who have Androgenetic alopecia are genetically sensitive to DHT [Dihydrotestosterone]. Their hair follicles are sensitive to the male hormone DHT and over a period of time the hair follicles will stop growing any hair.

In short, hair follicles affected by the male hormone DHT somehow forget the procedure to re-grow hair. Their lifespan becomes short and they do not grow any further hair.

Male pattern baldness can be easily identified by the receding hairline and thinned crown. Very often, hair is first lost around the temple area and gradually patches appear at the front and top of the scalp. The back and side area of scalp are unaffected and seems to have no affect to the male hormone DHT.

To determine how far your hair loss has progressed, the Norwood is used. [See the image below]

Image source: AHLA