Erectile Dysfunction

Ginkgo biloba. Ginkgo has also emerged as a possible treatment for ED, especially ED associated with the use of modern antidepressant medications. The newer selective serotonin reuptake inhibitor (SSRI) class of antidepressants, in particular, has been associated with a relatively high degree of sexual dysfunction. While depression itself is often associated with decreased libido, modern treatments for depression may add to the problem. For instance, a recent study conducted in Europe estimated that about one third of all patients taking SSRI antidepressants suffered from some degree of drug-induced sexual dysfunction (Williams VS et al 2006). It has been proposed that this effect is mediated in men by drug-induced increases in the amount of serotonin in the central nervous system, which in turn inhibits physiological mechanisms involved in penile erection (McKenna K 1999).

An open trial of ginkgo for the treatment of antidepressant-induced sexual dysfunction concluded that an impressive 76 percent of men experienced improved sexual function after taking 120 to 240 mg ginkgo extract daily for one month. “Ginkgo biloba generally had a positive effect on all four phases of the sexual response cycle: desire, excitement (erection and lubrication), orgasm, and resolution (afterglow),” wrote the authors. They speculated that this effect might be caused by ginkgo’s ability to improve dilation of peripheral blood vessels or to modulate central serotonin receptor factors (Cohen AJ et al 1998).

Icariin. This glycoside is found in horny goat weed. It has been studied for its ability to enhance erections and improve sexual performance by affecting nitric oxide synthesis. In one animal study, icariin administered to castrated rats improved a number of measures that are connected to erectile health, including nitric oxide levels and intracavernosal pressure (Liu WJ et al 2005). These results have been supported by additional studies that have found that icariin can improve intracavernosal pressure and thus enhance erectile quality (Tian L et al 2004).

Testofen. Testofen is a standardized extract of fenugreek. A number of animal studies conducted by Gencor Pacific have shown that Testofen can raise testosterone levels more than placebo can and to a degree comparable to the prescription drug Viagra®. In another animal study conducted by Gencor, Testofen produced activity almost equivalent to testosterone in castrated rats. The product is under investigation in human beings.

Tribulus terrestris and DHEA. ED has been associated with declining levels of dehydroepiandrosterone (DHEA), an important hormone that tends to be depleted steadily with age (Basar NM et al 2005; Feldman HA et al 1994). Studies have shown that supplemental DHEA may be helpful in relieving symptoms of ED in patients with initially low DHEA levels (Reiter WJ et al 1999, 2001).

An increase in bioavailable DHEA may underlie the efficacy of another herbal remedy for impotence, Tribulus terrestris. Also known as puncture vine, Tribulus contains the active ingredient protodioscin, which is reportedly converted to DHEA in the body (Adimoelja A 2000). This DHEA-boosting activity may account for puncture vine’s reputation as an aphrodisiac in its native Europe and Asia. While some animal studies appear to confirm the ability of Tribulus to improve sexual functioning, no reliable human trials have taken place (Gauthaman K et al 2002, 2003; Adaikan PG et al 2000).

Weight Loss: Restoring Function

Lifestyle changes may be sufficient to reverse ED, especially when ED is associated with obesity. Epidemiological studies indicate that physical activity and leanness are associated with a reduced risk for ED. A study published in the prestigious Journal of the American Medical Association found that about one-third of obese men with confirmed ED were able to improve their sexual function after losing weight and increasing physical activity over the course of two years (Esposito K et al 2004).

In a randomized trial involving 110 obese Italian men, test participants lost more than 10 percent of their initial body weight and roughly quadrupled the amount of time they spent exercising each week. Serum markers of inflammation, including C-reactive protein and interleukin-6, also decreased significantly. After two years, about one third of these initially obese participants reported significantly better sexual function than did control participants, whose weight and exercise levels remained roughly constant (Esposito K et al 2004).

Of course, this study also shows that lifestyle changes may not be feasible, or adequate, to reverse established ED in all cases. Fortunately, some safe, natural alternatives are available whose clinical data support their benefits for sex and health.

A Word of Caution

Some so-called aphrodisiacs may actually do more harm than good. “Spanish fly” is a case in point. Derived not from a fly but from the blister beetle, Spanish fly, or cantharidin, is far more likely to cause painful poisoning than pleasurable erection. It should be avoided (Sandroni P 2001; Karras DJ et al 1996).

Product Availability

All the nutrients and supplements discussed in this section are available through the Life Extension Foundation Buyers Club, Inc. For ordering information, call anytime toll-free 1-800-544-4440, or visit us online at www.LifeExtension.com.

The blood tests discussed in this section are available through Life Extension National Diagnostics, Inc. For ordering information, call anytime toll-free 1-800-208-3444, or visit us online at www.LifeExtension.com.