|Dihydrotestosterone (DHT) is a biologically active metabolite of the hormone testosterone, formed primarily in the prostate gland, testes, hair follicles, and adrenal glands by the enzyme 5α-reductase. Testosterone, a male hormone, is converted into DHT or Dihydrotestosterone in various tissues of the body and the skin. The enzyme 5 alpha reductase converts testosterone into its more potent form DHT. DHT is the most potent of the male steroid hormones, with an activity that is 10 times that of testosterone. Because of its relatively lower potency, testosterone is sometimes considered to be a prohormone.
Dihydrotestosterone belongs to the class of compounds called androgens, also commonly called androgenic hormones or testoids. DHT is thought to be approximately 30 times more potent than testosterone. DHT hormone stimulates cell growth in the tissue that lines the prostate gland (the glandular epithelium) and is the major cause of the rapid prostate enlargement that occurs between puberty and young adulthood. DHT is a prime suspect in prostate enlargement in later adulthood. DHT is also an important contributor to other characteristics generally attributed to males, including muscular growth, facial and body hair growth, and deepening of the voice. DHT also seems to play a role in the development or exacerbation of benign prostatic hyperplasia, or BPH, and prostate cancer, though the exact reason for this is not known. Women with increased levels of DHT may develop certain androgynous characteristics typical of men, including hair above the lip, a deepened voice, and increased muscular growth.
DHT is the androgen hormone that triggers hair loss in androgenetic alopecia. When hair follicles that are genetically programmed to be receptive to DHT receive the DHT message over a long enough period of time, the follicle begins to produce less hair. In male pattern baldness, each successive growing/shedding cycle results in the production of finer and finer (less thick) hairs by the affected follicles, until the hair finally is never able to break the surface of the skin. On the face and chest, DHT stimulates the growth of thick curly hair. This contrasts with its effect on the scalp where it makes hair thin out and eventually kills off the follicles altogether. Once DHT binds to large numbers of receptors of the hair follicles of the scalp, the follicles gradually shut down and eventually become dormant.
5α-reductase inhibitors is used for treatment of problems stemming from overproduction of DHT, which includes finasteride and dutasteride. Currently, DHT supplementation is not used as a treatment for DHT or androgen deficiency. Alternative treatments used to inhibit DHT include dietary supplementation with, or topically administered preparations of, saw palmetto berry extracts, which appear to have some inhibitive effect on DHT production or effectiveness. The chemical equol, derived by consuming soy foods rich in soy isoflavones by persons with certain digestive-tract bacterial flora, appears to have an androgen-inhibitive effect; however persons without the necessary equol-producing bacterial flora will receive no benefit from that potential therapy.