Men’s sexual health: The testosterone connection

As men age, there is often a decline in levels of testosterone. Research1 indicates that testosterone levels in men fall progressively with age and that a significant percentage of men over the age of 60 years have serum T levels that are below the lower limits of young adult men (age 20-30 years).

Some studies2 show that men experience a gradual and progressive decline in total testosterone levels that take place at a rate of approximately 1 percent per year beginning in their 30s, while other studies3 show an average annual decline of 1–2 percent total T levels, with an even more rapid decline in free T. Ramifications of this decline in testosterone include a reduction in libido and sexual function, interfering with intimacy in romantic relationships, while also eroding self-confidence and quality of life. Consequently, it is no surprise that prescriptions for testosterone (injections and gels) have become more and more common in men 50 years and older. This article will cover two nutraceuticals, shilajit and ashwagandha, which have also been shown help increase testosterone levels.


Secreted from sedimentary rocks (largely in the Himalayas) shilajit is a pale-brown to blackish-brown exudate, composed of rock humus, rock minerals and organic substances that have been compressed by layers of rock mixed with marine organisms and microbial metabolites.4 Said to carry the healing power of these great mountains,5 shilajit is an important drug of the ayurvedic materia medica, and is used extensively by ayurvedic physicians for a variety of conditions, including the management of male reproductive disorders.6,7 Furthermore, shilajit has an extensive history of use in ayurvedic medicine as an aphrodisiac,8,9,10,11,12 and its safety has been well documented based on animal and human studies.13

In a 90-day clinical trial,14 the effects of 100 mg shilajit (as PrimaVie purified shilajit) twice daily in 28 infertile male patients with oligospermia (a condition with low sperm concentration). Total semenogram (sperm analysis) and serum testosterone, luteinizing hormone, follicle-stimulating hormone were measured before and at the end of the treatment. In addition, malondialdehyde (MDA), a marker for oxidative stress, content of semen and biochemical parameters for safety were also evaluated. Results showed significant (P < 0.001) improvement in various parameters, including 37.6 percent increase in sperm mobility, 61.4 percent increase in total sperm count, 12.4-17.4 percent increase in motility (after different time intervals) and 18.9 percent increase in normal sperm count. There was also a significant 18.7 percent decrease of semen MDA content, a significant 23.5 percent increase in serum testosterone (P < 0.001) and 9.4 percent increase in FSH (P < 0.05) levels. Hepatic and renal profiles indicated that shilijit safety.

In addition to efficacy in an oligospermic population, the effects of 250 mg/twice daily shilajit (as PrimaVie purified shilajit) on male androgenic hormones were also tested in 98 healthy male volunteers (45-55 years) in a 90-day, randomized, double-blind, placebo-controlled clinical study. On days 0 (baseline), 30, 60 and 90 total and free testosterones, LH, FSH, DHEAs were measured from fasting blood of each volunteer. Results showed that the PrimaVie treated group experienced an increase of testosterone levels on days 30 (6.82 percent), 60 (3.09 percent) and 90 (20.45 percent, P<0.05) compared to baseline.

By contrast, there was a decreasing trend of testosterone levels in the placebo group (p<0.05). Testosterone levels in the PrimaVie group were significantly better those of the placebo group at day 90 (P<0.05). Levels of free testosterone in the PrimaVie group significantly increased by 19.14 percent (p<0.05), which was significantly higher than the placebo group (P<0.05). In addition, FSH levels significantly increased (p<0.004) in the PrimaVie group, which was significantly better than the placebo group on day 90. Also, DHEAs increased by 31.35 percent on day 90 in the PrimaVie group, which was significantly higher than baseline or the placebo group (p<0.05).

Despite the fact that the two studies summarized above were conducted on oligospermic and healthy male populations using 200 mg and 500 mg shilijit daily, the increase in T levels was markedly similar: 23.5 percent and 20.45 percent, respectively. This similarity suggests the potential for a greater likelihood of efficacy in different populations.


The root of ashwagandha (Withania somnifera) is a small, woody shrub found growing in Africa, the Mediterranean and India, has been used in ayurvedic medicine16 for more than 3,000 years, and was described by Dioscorides (78 AD) in his book Kitab-ul-Hashaish.17 The therapeutic actions of ashwagandha have been said to include tonic, aphrodisiac, narcotic, diuretic, anthelmintic, astringent, anti-inflammatory, sedative, alterative, thermogenic and stimulant.18,19 In the literature, steroidal lactones known as withanolides have been discussed as important active compounds in ashwagandha,20 although a full spectrum extract (KSM-66) has also demonstrated significant efficacy in human clinical research.21,22 In fact, it is that full-spectrum extract about which research will be discussed in this article.

To evaluate the effects of ashwagandha root extract (KSM-66 ashwagandha, 675 mg/d in three doses, n=21) or placebo (n=25) on spermatogenic activity and serum hormone levels in 46 patients with oligospermia, a 90-day, two-arm, double-blind, randomized, placebo-controlled, parallel-group study23 was conducted. Semen parameters and serum hormone levels were estimated at the end of 90-day treatment. Results showed that there was a 167 percent increase in sperm count (P<0.0001), 53 percent increase in semen volume (P< 0.0001) and 57 percent increase in sperm motility (P<0.0001) on day 90 from baseline. The improvement in these parameters was minimal in the placebo-treated group.

Furthermore, a significantly greater improvement and regulation were observed in serum hormone levels with the ashwagandha treatment as compared to the placebo. Serum testosterone increased significantly by 17 percent (P<0.01) and LH by 34 percent (P< 0.02), following treatment with ashwagandha root extract, as compared to the baseline (Day 0) values of these parameters.

To examine the effects of the KSM-66 ashwagandha root extract (one 300 mg capsule, twice daily) or placebo on muscle strength and endurance, size and recovery, testosterone, and body fat in 50 healthy and physically active males (18-45 years of age, n=25 for each group) with little experience in resistance training, an 8-week randomized, prospective, double-blind, placebo-controlled clinical study24 was conducted. Creatine kinase (CK) was assessed as a biomarker of recovery from muscle injury. Following baseline measurements, subjects underwent resistance training for eight weeks thereafter, measurements of the specific parameters were repeated at the end of week 8 (completion of study).

The results were that both muscle strength (bench press) and muscle size (arm), increased significantly in the ashwagandha group as compared to the placebo group (P<0.001 and P<0.05, respectively). There was also a significant increase of 15 percent in the concentration of total serum testosterone in the ashwagandha group at week eight of the study period as compared to the corresponding baseline value (P<0.05).

The increase was significant also as compared to the placebo group (P<0.01). In addition, the expected increase in creatine kinase (CK) between 24 and 48 hours following exercise was significantly lower in the ashwagandha group compared to placebo (P<0.05), and the reduction in body fat percentage was significantly greater in the ashwagandha group compared to placebo (P<0.05).


Given the prevalence of decreased testosterone in aging men, the use of these nutraceuticals offers an option for helping to increase levels of this hormone, with a high margin of safety. VR




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