Natural Approaches to Boost Testosterone and Suppress Estrogen
Nutrients function by increasing testosterone availability, often by affecting testosterone's interaction with SHBG or by decreasing its aromatization (conversion) into estrogen. Natural supplements can complement hormone replacement therapy. For people who choose not to (or should not) use hormone replacement therapy, nutrients can be a vital part of a comprehensive program to reduce the impact of aging on the systems of sex hormone production, regulation, and metabolism. Nutritional therapy also has a role in preventing diseases of the male reproductive tract, such as prostate cancer and benign prostatic hyperplasia (BPH). More specific information on these diseases can be found in the chapters "Prostate Cancer" and "Benign Prostatic Hyperplasia."
The following is a list of nutrients that are part of the Life Extension Foundation's comprehensive male hormone modulation program:
Zinc. Zinc is related to testosterone levels. In one animal study, rats subjected to an acute swimming test were either supplemented with zinc or placebo. The study showed that zinc supplementation led to significant increases in testosterone levels and may help in athletic performance (Kaya O et al 2006). Among humans, zinc supplementation in a group of male wrestlers prevented the depletion of testosterone after exertion (Kilic M et al 2006). Additional studies have suggested that zinc is important to the synthesis of testosterone (Ali H et al 2005).
Chrysin. A bioflavonoid called chrysin has shown potential as a natural aromatase inhibitor (Kellis JT Jr et al 1984). Chrysin can be extracted from various plants and is found in high concentrations in honey. Bodybuilders have used it as a testosterone-boosting supplement because, by inhibiting the aromatase enzyme, less testosterone is converted into estrogen. Although chrysin is a known inhibitor of aromatase, in one study it did not result in the expected increase in testosterone levels (Gambelunghe C et al 2003). This may be because of poor intestinal absorption of chrysin (Walle UK et al 1999). The Life Extension Foundation has identified a novel supplement called piperine that increases the bioavailability of chrysin.
Carnitine. Carnitine is an amino acid derivative that may be more active than testosterone in aging men who have sexual dysfunction and depression caused by an androgen deficiency (Cavallini G et al 2004). Both testosterone and carnitine improve sexual desire, sexual satisfaction, and nocturnal penile tumescence, but carnitine is more effective than testosterone in improving erectile function, nocturnal penile tumescence, orgasm, and general sexual well-being. Carnitine was better than testosterone at treating depression (Cavallini G et al 2004).
Muira puama. Muira puama is a South American folk medicine derived from a shrub, Ptychopetalum olacoides, which grows in the Amazon region of Brazil. Also called marapuama and "potency wood," it is considered an aphrodisiac and an effective treatment of impotence. Because of its purported libido-enhancing properties, muira puama has been the subject of two published clinical studies by Dr Jacques Waynberg, an eminent medical sexologist and author of 10 books on the subject.
The first study, conducted at the Institute of Sexology in Paris under Dr Waynberg's supervision, consisted of examining the effect of muira puama on 262 men who complained of lack of sexual desire or inability to attain or maintain erection. After receiving 1.5 grams (g)/day of muira puama for 2 weeks, 62 percent of the patients with loss of libido rated the treatment as having a dynamic effect, and 52 percent of patients with erectile dysfunction rated the treatment as beneficial (Wright JV et al 1999).
Dr Waynberg's second study, entitled "Male Sexual Asthenia," focused on sexual difficulties associated with asthenia, a deficiency state characterized by fatigue and loss of strength, both symptoms of a testosterone deficiency. The study population consisted of 100 men older than 18 years who complained of impotence and/or loss of libido. A total of 94 men completed the study, and their conditions were evaluated. Muira puama treatment led to significantly increased frequency of intercourse for 66 percent. Of the 46 men who complained of loss of desire, 70 percent reported intensification of libido. The stability of erection during intercourse was restored in 55 percent of patients, and 66 percent of men reported a reduction in fatigue. Other reported beneficial effects included improvement in sleep and morning erections (Waynberg J 1990).
Cruciferous vegetables. Cruciferous vegetables, such as broccoli and cauliflower, contain isothiocyanates and glucosinolates, which act as antioxidants and potent inducers of phase 2 proteins believed to suppress prostate cancer formation (Kris-Etherton PM et al 2002; Talalay P et al 2001).
Quercetin. Wine contains antioxidant polyphenols and quercetin. One study showed that red wine inhibited aromatase. The study attributed this effect to the quercetin and other ingredients (Eng ET et al 2002). In human colon cancer cells, quercetin has been shown to inhibit local synthesis of estrogen by inhibiting aromatase (Fiorelli G et al 1999).
Saw palmetto and nettle extracts. These two supplements are commonly used to reduce symptoms of BPH. In Europe, saw palmetto (Serenoa repens) has been used extensively as a drug for some time. Saw palmetto's clinical benefits for prostate enlargement include: