Monday, November 22, 2010

DHT Safer Than Previously Thought: High Blood DHT does not Induce Prostate Cancer

Regular visitors of the SuppVersity will know that the stigmatization of DHT goes without reasonable and conclusive scientific research. In their editorial to the Annals of Internal Medicine Swerloff & Wang (Swerloff. 2010) conclude from the results of more recent studies into the various effects of DHT on different tissues:
In normal men, serum DHT levels are approximately 10% of the serum testosterone levels, whereas intraprostatic DHT levels are much higher than serum levels, with the intraprostatic DHT–testosterone ratio being 7 to 8 (12). Although the authors did not measure DHT levels in
the prostate after DHT administration
, Page and coworkers (13) recently reported that prostatic DHT levels did not increase when pharmacologic doses of DHT were administered (Page S. Personal communication.). These findings are consistent with those of Marks and colleagues (12), which demonstrated that administration of testosterone to mildly testosterone-deficient men increased serum testosterone levels but did not increase either prostatic DHT or testosterone concentrations. Thus, it seems that the amplifying 5alpha-reductase system is so efficient in regulating intraprostatic DHT levels that substrate (for example, testosterone) concentrations are limiting only at very low levels. Furthermore, the ability of the 5alpha-reductase system to produce high tissue levels of DHT in organs, such as the prostate, indicates that even high levels of DHT in the blood remain much lower than the levels reached in the prostate and thus have little influence on prostate growth. In contrast, high levels of DHT in the blood will act as a hormone and thus produce real effects in tissues with less dominant testosterone to DHT-amplifying systems, such as muscle, fat, and bone marrow. Although the present study was not adequately powered to definitively answer the question of long-term safety of testosterone use, these data do show that a 10-fold increase in serum DHT levels had no significant effects on prostate size, serum DHT, and International Prostate Symptom Score, suggesting that the modest increases of serum DHT seen after testosterone treatment may not have a clinically significant effect on prostate health.
So after all, this means that
  1. you do not have to take Finasterid or other side-effect-loaden bullsh* if you are on TRT
  2. you may benefit from the positive effects on libido, alpha-male feeling and probably muscle growth of reasonably elevated DHT-levels without having to worry about your prostate
  3. you better not believe every "scientific fact" that is covered in mainstream media