Do you know if there has been any study on male pattern baldness and the amount of dihydrotestosterone produced in the body?
Anyways, I have a theory of that the prostate plays a big role in male pattern baldness. The prostate is an organ that produces 5-alpha-reductase and it also varies greatly in weight. I assume that a heavy prostate should produce more 5-alpha-reductase than a lighter one. Finasteride inhibits 5-alpha-reductase production and this works against developing male pattern baldness. Also, finasteride decreases the size of the prostate by roughly 18%. It's seems logical that the prostate is either shrunk because its function to convert testosterone to dihydrotestosterone decreases in activity, or because dihydrotestosterone levels in the prostate are reduced by 85-90% upon taking finasteride.
I've also come across a study which suggests that men who have developed male pattern baldness are at a greater risk at developing prostate cancer:
Our analysis indicates that frontal plus moderate vertex baldness at age 45 years is associated with an increased risk of aggressive prostate cancer and supports the possibility of common pathophysiologic mechanisms. (
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4314593/)
Could the reason to this be because men who develop male pattern baldness have bigger prostates? It's interesting to note that men who had a prepubertal castration possibly never develop prostate cancer. Also, these prepubertal castrated men halt their prostate development entirely.