Dihydrotestosterone hormone DHT natural blockers, hair loss, effect of supplementation on bone mineral density by Ray Sahelian, M.D.
June 17 2015

DHT dihydrotestosterone is an androgen from testosterone through the action of the enzyme 5-alpha-reductase, whose concentrations are highest in the peripheral tissues (genital skin and hair follicles). Dihydrotestosterone is primarily responsible for the physical changes that occur during male sexual maturation and is thought to be related to sex drive as well as erectile capabilities in men. In addition, dihydrotestosterone has been associated with benign prostate hypertrophy (BPH) and prostate cancer.

Bone density effect
Dehydroepiandrosterone replacement therapy in older adults: 1- and 2-y effects on bone1,2,3
Am J Clin Nutr, 2009. Edward P Weiss, Krupa Shah, Luigi Fontana, Charles P Lambert, John O Holloszy and Dennis T Villareal. From the Division of Geriatrics and Nutritional Sciences, Department of Internal Medicine, Washington University School of Medicine, St Louis, MO; the Department of Nutrition and Dietetics, Saint Louis University, St Louis, MO; and the Division of Food Science, Human Nutrition and Health, Istituto Superiore di Sanitá, Rome, Italy.
The objective was to determine whether DHEA supplementation in older adults improves BMD when co-administered with vitamin D and calcium. In year 1, a randomized trial was conducted in which men and women aged 65–75 y took 50 mg/d oral DHEA supplements or placebo. In year 2, all participants took open-label DHEA (50 mg/d). During both years, all participants received vitamin D (16 µg/ day) and calcium (700 mg/ day) supplements. In men, no difference between groups occurred in any BMD measures or in bone turnover markers during year 1 or year 2. The free testosterone index and estradiol increased in the DHEA group only. In women, spine BMD increased by 1.7% during year 1 and by 3.6% after 2 y of supplementation in the DHEA group; however, in the placebo group, spine BMD was unchanged during year 1 but increased to 2.6% above baseline during year 2 after the crossover to DHEA. Hip BMD did not change. Testosterone, estradiol, and insulin-like growth factor 1 increased in the DHEA group only. In both groups, serum concentrations of bone turnover markers decreased during year 1 and remained low during year 2, but did not differ between groups. Dehydroepiandrosterone supplementation in older women, but not in men, improves spine BMD when co-administered with vitamin D and calcium.

Dihydrotestosterone and hair loss
Male and female pattern hair loss is thought to be due to the effects of dihydrotestosterone on genetically predisposed hair follicles. Binding of dihydrotestosterone to the hair follicle results in gradual miniaturization of the hair and eventual hair loss. Finasteride is a 5alpha-reductase inhibitor approved for the treatment of male pattern hair loss. Originally approved for the treatment of benign prostatic hypertrophy in 1992, its approval was expanded in 1997 to include the treatment of androgenetic alopecia in men at a dose of 1 mg/day. Finasteride inhibits 5alpha-reductase, thereby prohibiting the conversion of testosterone to dihydrotestosterone, which is implicated in the development of hairless in some men. Reduction in dihydrotestosterone results in a significant improvement in subjective and objective assessments of hair growth and density.

Natural and herbal dihydrotestosterone blockers
There are certain herbs that may be natural dihydrotestosterone blockers, but, at this time, no long term studies have been done to determine if taking certain herbs has an influence on hair growth. Saw palmetto may be a partial dihydrotestosterone blocker in prostate tissue but it remains to be seen how potent it is when taken as a dietary supplement.

Dihydrotestosterone versus testosterone - how are they different?
Testosterone influences overt masculinization in the adult male, and dihydrotestosterone influences prostatic growth, acne, facial beard, and male pattern baldness. Inhibition of dihydrotestosterone in adults results in prostatic shrinkage and symptomatic relief in many men, without the serious side effects seen with conventional androgen-deprivation therapy.

Questions
Q. I take finasteride to block testosterone to dihydrotestosterone. I have noticed my libido has dropped a little. Is this due to the dihydrotestosterone blocker use?
   A. Most likely. Blocking the conversion of testosterone to dihydrotestosterone does appear to negatively influence libido in some men.