DHT
DHT is a derivative hormone (metabolite) of testosterone that has been shown to be critical to the initiation and progression of follicular miniaturization and eventual destruction of hair follicles in male pattern baldness. DHT is a steroid hormone just like testosterone but with greater affinity for the androgen receptor. Converting testosterone to DHT thus increases many of its effects.
While the mechanism by which DHT is involved in hair loss is not confirmed, many dermatologists and research scientists specializing in hair loss believe DHT molecules may diffuse into the interior of hair follicle cells (the cytoplasm or cytosol) and bind with androgen receptors. This complex, both the receptor and the DHT molecule, then enters the nucleus of the cell. In the nucleus of the hair follicle cell this complex could then alter the rate of protein synthesis in men who are genetically predisposed to baldness.
However, DHT also plays an important role in the functioning of the central nervous system (the brain), the testicles and prostate, and almost everything but muscle tissue. In muscle tissue testosterone is the dominant hormone, which is why some bodybuilders inject testosterone derivatives to aid in muscular development.
[edit] Side Effects
Inhibiting DHT has many possible side-effects.
- Propecia (and other products containing Finasteride) cause a rise in testosterone levels because testosterone that would normally be converted into DHT remains testosterone. Continual high levels of testosterone in the body could possibly have negative side effects.
- Artificially low levels of DHT in the body could cause some unwanted conditions. DHT is an antagonist of estrogen. Men’s bodies also produce the female hormone estrogen in the adrenal glands, although this is just one-tenth of the estrogen that premenopausal women produce in their ovaries. By reducing DHT with drugs, a man’s protection from the effects of estrogen may also be reduced. This could result in gynecomastia.
- Even though both Finasteride and Dutasteride were developed to combat benign prostatic hyperplasia by reducing DHT in prostate tissue, some scientists question the wisdom of using these 5-alpha-reductase inhibitors in younger men who have no problem with their prostates. A research chemist, Pat Arnold, says “Evidence is mounting that the existence of a high estrogen/androgen ratio – a condition common in older men – is highly correlated with the development of benign prostatic hyperplasia.” However, in apparent contradiction, individuals with 5-alpha-reductase deficiency (and thus a similar hormonal profile to users of DHT inhibitors) do not experience BPH.