The Role of Testosterone in Male Health:While testosterone production gradually declines after age 30 there are other factors under our control that further lowers usable testosterone and negatively influences our health. By understanding and treating these we can reduce our biological age as opposed to our chronological age. Common symptoms of low testosterone include; low libido, erectile dysfunction, weight gains, loss of muscle mass, pessimism, depression, irritability, fatigue, poor memory, sleep problems and a higher incidence of cardiovascular disease, heart attacks, prostate enlargement and cancer, osteoporosis and senile dementia.
- Having lower than normal testosterone for ones age can contribute to many conditions of poor health.
- While testosterone does decline naturally with age there are several other factors that reduce the level of free testosterone (also known as bioavailable testosterone) and these are under our control.
- Tongkat Ali (Eurycoma longifolia) is the most important natural herb available today to increase free testosterone and scientific research over the past 20 years confirms this.
Studies have noted that testosterone levels and sperm count have been declining in many parts of the world as a result of poor diets, stress and sedentary lifestyles combined with rising estrogen exposure in foods and the environment. testosterone also becomes bound to serum globulin and is not available to the cell receptor sites where it is needed to initiate sex-stimulating centers in the brain. The component in the blood that renders free testosterone inactive is called sex hormone binding globulin (SHBG). Aromatase an enzyme produced in skin, fat tissue, brain & adrenals also converts testosterone into estrogen (estradiol), further educing available testosterone. While normal in small amounts, aromatization is accelerated with excess abdominal belly fat. For testosterone to produce its positive health enhancing effects, it must be kept in the "free" form in the bloodstream. Bound testosterone is unable to be picked up by testosterone receptors on cell membranes. Estrogen levels of the average 54-year-old man are often higher than those of the average 59-year-old woman. While some estrogen is a necessary hormone for men, too much contributes to a wide range of health problems, such as excess weight gains and prostate enlargement. Due to similarities in chemical structure, high serum levels of estrogen also trick the brain into thinking that enough testosterone is being produced, thereby slowing the natural production of testosterone. The testosterone level may also be affected unknowingly by various medications and alcohol.
For aging men, it may be desirable to initiate lifestyle and supplementary regimes to reduce excess levels of SHBG and estrogen while boosting free testosterone. Testosterone levels are supported by regular exercise (especially resistance or weight training exercise), reducing weight with diets that reduce all refined carbohydrates and processed junk foods and specific foods and herbal supplements that promote free testosterone and counter the conversion of Testosterone to Estrogen (see our dietary recommendations here). A professional health regime must also supports adrenal function, blood sugar regulation, reduce inflammation and assist detoxification for maximum results.
The benefits of maintaining optimum testosterone levels are many, including;
- Improve muscle mass and strength
- Decrease body fat
- Increase bone mineral density
- Thicken body hair and skin
- Improve sexual desire
- Boost energy
- Decrease irritability and depression
- Improve cognitive function and confidence
Tongkat Ali (Eurycoma longifolia) Medicinal Research
Tongkat Ali is a small rain forest tree common to Malaysia, Borneo and northern Sumatra in Indonesia. The long taproot of the plant has been used traditionally by the many different indigenous people of the region for a wide variety of conditions, the most common being low sexual energy and fevers. The name Tongkat Ali in Malay means “Ali’s walking stick” in reference to its famed aphrodisiac properties. Beginning in 1993, scientists from various Universities and research institutes around Malaysian began conducting scientific trials to evaluate whether Tongkat Ali had any scientific basis for its reputed aphrodisiac and sexual enhancing effects. These various studies started to be presented at local biotechnology and medicinal plant seminars after 1994. In these early studies Tongkat Ali was tested both on its effects on cellular activity in the test-tube as well as studies on live animals. These landmark studies on the effects of Tongkat Ali on living cells in the test-tube showed an increased rate of glycolysis (60% increased), an increase in ATP production (80%) observed in liver homogenates and an increase in cGMP and cAMP by 60% (this effect was compared to the action of sildenafil citrate or Viagra and was found to be similar). These results showed that cellular energy was significantly enhanced.
The next step was to investigate the effects on human testicular cells and testosterone synthesis (J.M. Saad et al 1995). The interesting results showed that Tongkat Ali extract significantly improved testosterone levels, while the dehydrotestosterone, also known as the bad testosterone (as it is implicated in prostate enlargement and male pattern baldness) was reduced.
Further studies by J.M. Saad et al, on testosterone synthesis in mice, rats and rabbits demonstrated an impressive 320 to 479% increase in testosterone levels. In another study around this time Tongkat Ali extract was given to both male and female mice to determine the effects on mounting and litter size. While this test showed an increase in mounting frequency and testicular size increase in the male rats, what was interesting also was that the litter size increased by up to 76% with an increases ratio of male to female offspring, from the norm of 1:1 to 3:1.
From this and other subsequent studies it was shown that Tongkat Ali consumed orally significantly improved all aspects of sperm quality including volume and motility. Its fertility enhancement effects of Tongkat Ali extract was due to its effect of increasing sperm concentration, motility and velocity of movement, thus helping to increase the chances of sperms to penetrate the ova. As such a higher rate of fertilization causes an increase in offspring number. Also the capability of the extract to enhance energy production helps to increase the percentage of embryo development and increase the amount of embryo surviving up to the blastocyst stage.
It was however only in 1997 that studies on Tongkat Ali’s aphrodisiac effect were published in international scientific journals. This was achieved as a result of the studies conducted by the research team at University Science Malaysia (USM), principally Dr. Ang Hoi Hoon, with Tongkat Ali on rats and for the next 8 years or so they would go on to publish 1 or 2 studies each year, evaluating the aphrodisiac properties of Tongkat Ali.
The first of these studies, entitled “Eurycoma longifolia Jack enhances libido in sexually experienced male rats” was published in 1997. Dr. Ang and colleagues reported at the end of their study after dosing the male rats with increasing amounts of Tongkat Ali they observed a dose dependant increase in mounting frequency and summarized their report with the following statement, “this study provides evidence that Eurycoma longifolia Jack is a potent stimulator of sexual arousal in sexually vigorous male rats in the absence of feedback from genital sensation”.
The natural product research team at USM published in total 13 research papers between 1997 to 2004, assessing via varied controlled protocols the aphrodisiac action of Tongkat Ali crude extract in their laboratory rats. With each subsequent scientific study the rats responded to their incremental dosages of Tongkat Ali with enhanced sexual enthusiasm as monitored via behavioural characteristic such as: increased mounting, licking, anogenital sniffing, movement, exploration, rearing, and climbing. In addition, rats were assessed for levels of genital and non-genital grooming. Analysis of these types of behavioral elements has served as the method for investigating the anecdotal aphrodisiac properties of Eurycoma longifolia and administration of the crude extracts has been correlated in each study to indicate increased sexual performance of the treated animals. It was noted that no toxicity was reported in these studies at the dosages required to elicit a pharmacological effect.
With such positive results coming from the animal studies the next step was to conduct human studies and to date more than a dozen human clinical studies have been performed by researchers worldwide with Tongkat Ali. In the initial study in Malaysia by Dr Mohd. Ismail Tambi and colleagues, 10 males over 40 years of age who showed hypogonadism with testosterone level less then 11 were given a relatively low dosage of 2 x 2 (450mg) capsules of powdered Tongkat Ali root morning and evening for 1 month. By the end of the study serum testosterone showed increase in 50% of the participants.
In their follow-up study the effects of Tongkat Ali extract on testosterone, dehydroepiandrosterone (DHEA) and sex hormone binding globulin (SHBG) were investigated over a 3 week period using an intermediate dosage of 50 mg extract capsules, with 4 capsules taken each day. Also a questionnaire to determine improvement in quality of life and sexual response was given to the participants. The final results showed that 82% of the participants experienced improvements in physical, sexual and psychological well-being. While total testosterone was not significantly different, the DHEA levels had increased by 26% after one week to 47% after 3 weeks. SHBG levels had reduced in 66% of cases after 3 weeks. When SHBG decreases the free testosterone index (FTI) increases. The FTI analysis showed an increase in 39% of participants after 1 week and 73% of participants after 3 weeks.
In another study by Dr. Tambi et al, varying dosages of crude water extract were given to male volunteers and a more detailed blood profile was taken in regards to lipid profile, liver function, electrolytes, various tumor markers, immune reaction and hormonal levels. A sexual health questionnaire was also completed. The dosage of extract now given was 200 mg, 400 mg and 600 mg daily. In conclusion the majority of volunteers claimed improvements in sexual health and strength and blood tests showed that Tongkat Ali crude water extract was non-toxic even at high dosage of 600 mg extract daily in regards the test results on liver function, renal function, hematological profile, lipid profile, body electrolytes and immune system, as well as cancer markers, and specifically prostate specific antigen (PSA) was unchanged, signaling that dihydrotestosterone levels are not affected by Eurycoma longifolia administration. Interestingly HDL cholesterol (good cholesterol) showed a trend to improve as well as blood sugar levels. There was also an improvement in human growth hormone IGF-1 and thus Tongkat Ali may also modulate the release of IGF-1 from the liver. IGF-1 is known to increase muscle bulk, promote lean body and cell regeneration and acts as an anti-ageing hormone.
In an open study that measured the levels of testosterone in the saliva of 9 athletes between the ages of 26-52 years of age, the dosage of 100 mg of Tongkat Ali extract were given each day morning and night. Within a statistically short period of only 10 days each athlete had increased salivary testosterone between 15% to 50%.
The first blind controlled study was performed by researchers at the Department of Exercise Physiology at University Malaya. In this study 14 healthy men were given either 100 mg day crude Tongkat Ali water extract or placebo for 8 weeks. Simultaneously both groups performed an intensive strength-training program. Body composition, strength and arm circumference were measured before and after the test. The results of the study showed that fat free mass showed a significant improvement in the Tongkat Ali group but no improvement was made on placebo. Both groups showed body fat reduction, however the Tongkat Ali group had the highest compared to placebo i.e. 9.14% to 6.57% respectively. Both groups showed an increment in muscle strength, but again the Tongkat Ali group was higher than placebo i.e. 6.78% to 2.77 %. The arm circumference in the Tongkat Ali group increased significantly by 1.8 cm while there was no significant improvement in the placebo group. The researchers concluded that the increments in the Tongkat Ali group were consistent with increased testosterone levels and thus Tongkat Ali can be of use as an ergogenic aid of benefit in sports regimes.
Today we see the natural progression of these initial positive studies into finding the exact phytochemical markers in the herb responsible for it's multiple pharmacological effects as well as expanding the research into novel areas, well beyond its traditional uses. More than 80 peer review studies have been performed over the last 7 years, including additional human studies, investigating the following:
- Further confirmation of the testosterone, fertility and libido enhancing effects, including multiple human clinical studies.
- Studies on reversing the effects of estrogen in male rats.
- Multiple studies reversing androgen deficient osteoporosis.
- Reduction in stress in both male and female subjects and reduction in cortisol.
- Pharmacology of individual Quassinoids, including Eurycomanone.
- Natural alternative to Testosterone Replacement Therapy studies.
- Safety and toxicological studies showing a high degree of safety at prescribed therapeutic dosages.
- Anti cancer properties including against prostate cancer.
- Anti-inflammatory properties.
- Antiprotozoal studies.
Some of these studies may be accessed on PubMed here. Due to the nature of scientific research grants being predominantly funded for the purpose of pharmaceutical development, Tongkat Ali has been largely ignored for its role as a natural alternative to Testosterone Replacement Therapy. Tongkat Ali's long traditional use as an aphrodisiac does not allow for pharmaceutical patenting for its effects in male sexual function. Despite this, Tongkat Ali research has shown strong laboratory and clinical evidence as to its effectiveness in enhancing free Testosterone in ageing men and safety at normal prescribed dosages. Tongkat Ali is indeed a national treasure of Malaysia and a tribute to the ethnobotanical knowledge of its traditional healers.