Testosterone

Elevating Levels for Increased Energy and Overall Health

By Jason E. Barker, ND

The “male climacteric” was initially described in the medical literature in the 1940s in a report in the Journal of the American Medical Association.1 Better known as andropause, this condition has finally begun to receive attention from medical providers in the last few years. Initially, andropause was neglected due to much debate that questioned the validity of male hormonal decline. Because of this (and because it is often referred to with the confusing term of “male menopause”), andropause has until recently been fully neglected as an actual medical condition. To further worsen this situation, inconvenient and dangerous treatments, coupled with men’s notorious aversion to medical care—women seek medical care approximately 150 percent more often than men—had slowed attention on this condition.

Fortunately, andropause is becoming increasingly validated. Newer research demonstrates the safety and benefits of balanced testosterone levels.

Androgens and Male Health

Andropause refers to the condition of lowered androgen hormones, including androstenedione, dehydroepiandrosterone (DHEA), and testosterone. While we often refer to androgens as “male hormones,” they are found in women as well, although andropause is a term most often used to describe this hormonal decline in men.  The main androgen, testosterone, typically peaks in a man’s mid-twenties and then begins a slow decline thereafter. It is thought that each year after peaking, testosterone levels decline approximately 1.6 percent per year.

The testicles will produce roughly 95 percent of androgen hormones in a healthy young male. Most of this is testosterone, which is produced at roughly 10 milligrams per day. The adrenal glands also produce androgens in the form of dehydroepiandrosterone (DHEA). DHEA serves as a precursor to testosterone and the body will “use” it to bolster testosterone levels, among other uses. Roughly 98 percent of circulating testosterone is attached to proteins in the bloodstream (and is therefore technically “unavailable”), while the remaining 2 percent (known as “free” testosterone) provides for almost all of the physiologic activity of the hormone. Nearly half of the testosterone bound to blood proteins is strongly bound to sex hormone binding globulin (SHBG), while the other half remains weakly bound to other proteins such as albumin. The term “bioavailable” is used to refer to the free testosterone and the weakly bound testosterone component.2 Testosterone binds to SHBG with increasingly greater affinity as aging progresses, leading to a relative decrease in free testosterone.3 Age-associated estrogen elevation leads to greater SHBG production and greater binding, resulting in decreased amounts of “free” or “bioavailable” testosterone for use by the tissues.

When SHBG binds to testosterone in increasing amounts, a normal serum range of total testosterone can still be measured, despite the relative deficiency in bioavailable, or free testosterone. On the contrary, when excess androgens are present, SHBG tends to be low, leading to normal measurable levels of total testosterone and elevated levels of bioavailable testosterone.

Testosterone is subject to enzyme-induced transformation, a contributor to overall lowering of available testosterone.  One of the most commonly discussed enzymes involved in this conversion is 5 alpha-reductase. This enzyme is responsible for converting testosterone into dihydrotestosterone (DHT). DHT is thought to be responsible for the signature male health problems of prostatic hyperplasia and male pattern hair loss (in men that are genetically susceptible).4 DHT binds to androgen receptors with greater affinity than does testosterone. In fact, DHT binding is thought to be four times more potent (in terms of receptor activation) than testosterone in this regard.

Testosterone not transformed to DHT may then be converted by yet another enzyme known as aromatase. Also known as estrogen synthetase, it converts the testosterone molecule into the closely related, but vastly different estradiol molecule—an active estrogen metabolite. Aromatase is a cytochrome P-450 enzyme that catalyzes the rate-limiting step in estrogen synthesis, which is the conversion of androgens (androstenedione and testosterone) into estrogens. A significant amount of estrogen in men is produced via the aforementioned enzymatic conversions that most often occur in the adipose tissue, liver, and brain. Elevation of estrogens in men is a clinical concern that should be addressed as part of the course of testosterone evaluation in any man. Research is now focusing on the negative association between estrogen and male health and therefore deserves clinical attention. Targeted inhibition of aromatase will help prevent the transformation of testosterone into estradiol, potentially slowing testosterone loss and reducing estrogen-associated risks in male health including gynecomastia (male breast development), prostate disease and increased cancer risks, to name a few.

Symptoms of Andropause

As testosterone declines, symptoms include muscle loss, decreased bone density, increased coronary artery disease risk, decreased cognitive function, and myocardial infarction (heart attack) risk.5-6 (See Table 1) Testosterone itself plays a role in structural regulation of bodily proteins and suboptimal levels result in modest physical changes such as gradual weakening of muscles and bone loss while adipose tissue is gained with increasing ease.7 Observations by clinicians who treat men for andropause even suggest that rapid facial aging is the result of suboptimal testosterone levels. When testosterone continues to be low for years, memory lapses, impotence, generalized fatigue and irritability become common. Often the most notable (and alarming to patients) signs of andropause is decreased libido.8 On a mental-emotional scale, I have noticed in my clinical practice that andropause typically manifests as passivity, which then can manifest as lack of interest in sex, visual sexual stimulation, business pursuits and competitive sports and physical activity.

TABLE 1. Symptoms of Testosterone Deficiency

• Muscle loss

• Decreased bone density

• Increased coronary artery disease and heart attack risk

• Decreased cognitive function/dementia

• Fatigue

• Erectile Dysfunction/Decreased libido

• Mental changes including irritability, depression, anxiety

• Prostate issues

• Weight gain

• Insomnia

• Hot flashes

Other symptoms associated with andropause include erectile dysfunction, mood disturbances including depression, and tiredness, sleep difficulties, increased body fat, memory loss and difficulty with concentrating and even hot flashes. Clinically, I’ve noted numerous conditions that may confound the diagnosis of andropause including depression, renal failure, diabetes, liver cirrhosis, anemia, hypothyroidism, alcohol abuse/poor nutrition leading to decreased albumin levels, circadian rhythm of testosterone, vigorous athleticism, acute stress, surgery, severe burn, accidents, and antidepressants. Therefore, a wide-cast net of clinical suspicion must be adhered to when considering low testosterone as part of a clinical treatment plan.

Natural Solutions to Boost Testosterone

Fortunately, modulation of testosterone levels can be achieved on a variety of levels using naturally derived substances. Each substance has its own unique way of correcting low testosterone levels and all can be incorporated into a testosterone-boosting plan once andropause has been appropriately diagnosed. Clinicians should aggressively look for and address low testosterone and male hormone imbalance in men as young as 35. By initiating a plan that incorporates hormone balance, patients will be affected to a much lesser degree.

Nettle Root

The roots of the stinging nettle are useful for male hormone balance. Extracts known as lignans derived from the roots have the ability to bind sex hormone binding globulin (SHBG). When SHBG is bound, this may allow for more unbound, or free testosterone to be available for biological processes9 and this may prevent SHBG from binding to the prostate gland, which may prevent prostatic enlargement via SHBG binding.10 Stinging nettle root constituents also act to control the growth of prostatic cells and resultant symptoms.11-12 Nettle root also contains another constituent known as beta-sitosterol which has positive effects on testosterone levels and prostate health.13

Beta-Sitosterol

Beta-sitosterol is termed a plant sterol, or a cholesterol-like chemical derived from plants. Sterols, and more specifically beta-sitosterol, are also useful for male hormone balance and prostate health. Beta-sitosterol can inhibit the function of the enzyme 5 alpha-reductase, which works to convert testosterone to a metabolite known as 5 hydroxytestosterone.14-16 5 hydroxytestosterone may have negative effects on the prostate gland. By inhibiting the 5 alpha-reductase enzyme, beta sitosterol helps to maintain testosterone levels and prevent loss to testosterone metabolites that contribute to negative prostate health. (See the article on prostate health in this newsletter for more information).

Luteolin

Luteolin is a chemical constituent (flavone) derived from the herb Perilla frutescens. Luteolin works in the body to inhibit the aromatase enzyme responsible for transforming testosterone into estrogen. Luteolin may be considered a superior aromatase inhibitor in comparison to chrysin, another popular flavonoid-based aromatase inhibitor. Luteolin has proven to be superior in that it is well absorbed and distributed throughout the body,17-18 whereas chrysin, while an effective aromatase inhibitor in vitro, is very poorly absorbed into the body.19

Eurycoma Longifolia Jack

Eurycoma longifolia jack, also known as Tongkat Ali, grows as a shrub in Southeast Asia and has been used to improve male virility and sexual prowess as part of ongoing cultural tradition. New research demonstrates a scientific basis for its historical use due to the plant’s androgenic effects. The androgen-boosting effects of this plant include enhanced libido and sexual activity in laboratory animals.20-22 Anecdotal reports have also shown a beneficial increase in male testosterone levels as well. Because of these findings, Eurycoma longifolia has become a popular addition to male health regimens.

Myricetin

Myricetin is a flavonoid derived from grape skin extract. Myricetin works to inhibit the enzyme 5 alpha reductase, thereby preventing the conversion of testosterone to the prostate-damaging 5 hydroxytestosterone.23-24 Myricetin is thought to have greater bioavailability than other flavonoids, making it an excellent addition to a hormone targeted prevention program.

Conclusion

Reestablishing testosterone levels can prove to be highly beneficial for men suffering the effects of lowered hormone levels. Incorporating a supplement that uses the above-mentioned nutrients into a regimen for men at risk for hormone imbalance is a practical way to address this issue. Providing these nutrients before hormone imbalance becomes completely symptomatic will afford the patient a much lower risk of suffering from low-testosterone-associated conditions. Raising testosterone levels can lead to a reversal of symptoms such as fatigue, low libido, diminished drive and motivation as well as several physical conditions including reversal of adiposity, gains in strength, improved cognitive function, improved bone health and possibly heart disease prevention.25

References

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