One fact which goes against this theory is that many men with high levels of circulating DHT don’t lose their hair
It’s long been proven that Dihydrotestosterone (DHT) – an androgen hormone – is the leading cause of male pattern hair loss. DHT is a highly potent compound formed when testosterone combines with 5-alpha-reductase. This enzyme is found in the prostate, gonads, as well as the skin. In males about 70% of circulating DHT is formed this way, using about 10% of the testosterone produced each day.
DHT binds to specific androgen receptors at the base of the hair follicles. Inside the nucleus of each hair cell, a process begins where the healthy hair follicle is gradually miniaturised — the classic precursor to hair loss. The natural healthy hair cycle is disturbed, with the growth (or anagen phase) reduced, and the shedding (or telogen) phase extended.
There are several DHT blockers available , both pharmaceutical and natural (more below). Logically, if you could prevent DHT attacking scalp hair follicles you would eradicate 95% of hair loss. One fact which goes against this theory is that many men with high levels of circulating DHT don’t lose their hair. And it cuts both ways. Men who do lose their hair may not have particularly high levels of DHT. This has led trichologists to surmise that the sensitivity of the scalp to DHT is more critical to baldness than DHT levels themselves. But what could cause this variation in scalp sensitivity?
Auto-immune reaction?One possibility is that the sensitivity arises from an autoimmune reaction to our modern diet. Our bodies should contain a healthy balance of good and bad bacteria. Eating processed foods, causing the good bacteria to die off, may prevent the body from replenishing the levels of good bacteria in the gut. It's believed this can turn our immune system against our bodies in certain ways, such as increasing scalp sensitivity to DHT. This, in turn, could make our hair follicles more prone to miniaturisation. Other theories are that body pH and food allergies may have an effect on DHT scalp sensitivity, but there is little scientific evidence to back this up. Changing your diet may reduce DHT sensitivity, but this assessment shows that genetics is also a major determinant. We still don’t know whether genetic or androgenic factors play the biggest role in male pattern hair loss. The assessment concludes that DHT is the most aggressive androgen in promoting hair loss, but that measuring DHT levels is of little use. Assessing the genetic predisposition towards DHT scalp sensitivity is a far better indicator of baldness potential.
Finasteride is a popular prescribed drug for treating male pattern hair loss. It works by inhibiting production of the 5-alpha-reductase enzyme. According to this study, it can reduce systemic DHT levels by about 70%. Some men taking Finasteride have recorded adverse side effects, such as a lowered sex drive. To date though, and if used early enough, prescribed drugs like Finasteride and Minoxidil (a vasodilator) are the best way to prevent hair loss in men. Purported natural DHT blockers like green tea, saw palmetto and pumpkin seeds may work to some extent. Unfortunately there is no scientific evidence to back up claims these natural foods block DHT.
12 Best Natural DHT Blockers | Visible Regrowth in 16 Weeks?, by Will Hartfield, 24 May 2016
9 Ways To Reduce DHT Levels Naturally, by Will Hartfield, 9 May 2018