It's hard to dispute a causal link between DHT and hair loss. Stated well
here:
Firstly, studies show that DHT is higher in the scalps of men with thinning hair. Secondly, if a man is castrated, his testosterone (and DHT) levels plummet permanently. Men castrated before puberty (i.e., before their DHT levels spike) don’t go bald later in life. And thirdly, men with a genetic deficiency in an enzyme that converts testosterone into DHT in scalp tissues never develop pattern hair loss.
These are pretty indicting findings. Just look at the endpoints: men who never produce DHT never develop pattern hair loss. Men with higher amounts of DHT in their scalps have AGA. Based on these findings, DHT must play some causal role in AGA.
But the same article discusses how the DHT link might still be compatible with the scalp-tension hypothesis:
Question: If DHT causes pattern hair loss, how come eliminating DHT only stops AGA? How come it doesn’t lead to a full hair recovery?
...
Many researchers have hypothesized that this may be due to DHT’s relationship with scar tissue. In scalp tissues, the arrival of DHT seems to also remodel our scalps – causing increased disorganized collagen crosshatchings. In other words, scalp DHT causes fibrosis (or scarring).
In fact, balding scalp regions have four times the amount of excess collagen deposition (scar tissue) than non-balding regions. And as we’ve learned in scleroderma studies, where there’s scar tissue, hair cannot grow.
I've discussed it on the thread about hair loss I wrote last week.
Castrated men after puberty still develop male pattern baldness, even in complete absence of androgens. Men castrated a before puberty don't, as you stated.
The huge confusion about the DHT role in hair loss and prostate cancer is that DHT is elevated in the tissues in both cases, not in serum. And, as I said many times, it's because DHT has an anti-inflammatory effect on tissues. Everytime the body senses there's an inflammation, it signals the necessity of an increased concentration of DHT in that tissue.
Now, chronic elevation of DHT in the scalp provoke the thinning of blood vessels, also knows as calcification. No blood supply to the scalp = death of the follicles.
Would you say that DHT is the cause of hair loss then?
The simplest similitude is what happens with lactic acid accumulation in muscles after a heavy workout. Would you say that lactic acid is the cause of soreness or is it the heavy workout itself?
With all that being said, understanding what is causing the inflammation and the epigenetic in play here is quite complicated and could take years.
What I would say is to start finding ways to loosen your scalp in the meanwhile, while trying to find the reason behind your hair loss.
My hairline is basically intact, but I've lost hairs in the crown and mid section of the head, which are the the stiffest sections of my scalp and usually red and itchy.
