How does hair loss happen?
Have you ever wondered why some guys can go all their life with a full head of hair, while others start to go bald in college or even high school? Although there are multiple causes of hair loss, but this entry involves the most common cause of androgenic alopecia, which accounts for over 90% of hair loss.
Genetics play a major role in common age related hair loss (androgenic alopecia), and the process is still not completely understood. What is known (thanks to years of intense research by large pharmaceutical companies and academic universities) is that the the most common cause of hair loss, is due to the naturally occurring hormone dihydrotestosterone, DHT.
This hormone is a by product of a chemical reaction in the body, catalyzed by an enzyme called 5 alpha reductase, which essentially takes freely available testosterone and converts it to an altered form (hence the name Dihydrotestosterone) which is much more potent (in terms of affecting hair follicle growth.
A build up of DHT occurs over time, and it is thought that this build up leads to reduced hair follicle viability, which over time can cause the thinning of hair. This progressive atrophy of the hair follicle leads to reduced hair shaft diameter, and eventually the hair growth cycle produces less and less thick hairs until it the hairs on the scalp stop growing (leading to a bald head).
Much of the research among the matter has focused on the dht converting enzyme 5 alpha reductase [which actually a broad term for atleast 2 versions of 5 alpha reductase (5-AR)]