Dihydrotestosterone, or DHT, is a by-product of testosterone manufactured in the adrenal glands, hair follicles, testicles and prostate gland. Like testosterone, DHT is an androgen hormone, which means it plays a role in the development of male and female characteristics. Elevated levels of DHT contribute to enlarged prostate and hair loss, among other conditions. Certain herbs naturally block DHT synthesis. However, check with your doctor to get all the facts about these herbs and their potential side effects.
Eating raw pumpkin seeds is an old-fashioned remedy for the prevention of benign prostatic hyperplasia. In Europe, the German E Commission, a regulatory agency similar to the U.S. Federal Drug Administration, has approved the use of pumpkin seed and pumpkin seed oil for the treatment of prostate disorders. According to the “Physicians’ Desk Reference for Herbal Medicines,” the DHT-blocking effects of pumpkin seed stem from the presence of unusual amino acids such as cucurbitin, as well as several plant steroids, particularly delta-7-sterols.
Saw palmetto is one of the herbs that block DHT and has been studied extensively. Of particular interest to researchers is the presence of a specific plant sterol found in this herb called beta-sitosterol. The anti-androgen effects of this substance are directly related to the inhibition of an enzyme called 5-alpha-reductase type II, which is required by the body to convert testosterone into DHT in the prostate. The July 10, 2010, issue of Advances in Therapy featured an article reporting that low concentrations of a saw palmetto ethanol extract dubbed SPET-085 was as effective at inhibiting 5-alpha-reductase type II as finasteride, the standard prescription drug used to counter DHT conversion.
Research indicates that epigallocatechin-3-Gallate, or EGCG, one of the active constituents of green tea, also blocks the formation of DHT. A team of scientists from Harvard Medical School reported in the February 2003 issue of The Journal of Nutrition that green tea significantly reduced DHT and testosterone concentration in the blood. In another study published in The Prostate in 2009, British researchers found that EGCG decreased cell proliferation in prostate cancer cells by inhibiting DHT and promoting apoptosis, or cell death.
According to a study published in the Sept. 7, 2008, issue of the Journal of Cosmetic Dermatology, this botanical also blocks DHT by inhibiting 5-alpha-reductase type II, at least in cultured skin cells. The study authors reported that DHT conversion was prevented when giant dodder extract was added to culture dishes containing skin cells taken from mice with testosterone-induced alopecia.