The connection between prostate health and rising estrogen levels in men is still poorly understood in modern medicine and thus conventional pharmaceutical treatment is missing the root cause and as a result brings a lot of suffering with medications that further reduce an already declining testosterone level. This creates a viscous circle of male hormonal imbalance with ever declining testosterone and sexual function and rising estrogen and weight gains. By understanding the role of estrogen in prostate health then more fundamental changes may be made in terms of medication, diet and lifestyle to prevent this condition. The Malaysian rainforest herb Tongkat Ali is a part of this solution.
My interest began in studying the effects of Tongkat Ali on prostate health in the late 1990’s when I observed that many of the herbs used traditionally as rejuvenating male tonics are also employed in treating the urinary symptoms of Benign Prostatic Hyperplasia (BPH). This has been the case with herbs such as Damiana and Chinese Ginseng 43,44, as well as the current best-selling herbal medicine for BPH, Saw Palmetto21-32. Many men suffering from BPH also experience erectile dysfunction (ED) as a result of their condition as BPH and ED share a similar etiological relationship to ageing and its effects on the male hormonal system.
In Malaysia the herb Eurycoma longifolia (Tongkat Ali) has a long history of safe use for improving male sexual function and extensive studies conducted for the past 20 years has demonstrated effects on modulating male androgen synthesis. Studies to date have shown that Tongkat Ali extract produces an increase in available free testosterone with a reduction in sex hormone binding globulin (SHBG) with no increase in dihydrotestosterone (DHT), the androgen that has been held primarily responsible for causing enlargement of the prostate gland by modern medicine. Unfortunately, DHT is the strongest male androgen and any medication, synthetic or natural (such as Saw Palmetto) that blocks its conversion will likely produce a noticeable decline in sexual motivation. Thus the dilemma occurs that with increasing age men are more susceptible to benign prostatic hyperplasia and the medication commonly available, both natural and synthetic further reduce male androgens, libido and sexual function. Can Tongkat Ali prevent prostate enlargement while also supporting libido and sexual function in men?
Modern research into the mechanisms behind prostate enlargement.
A far more complex dynamic exists between the effects of ageing and various other factors (such as metabolic disorder and being overweight) on the ratios between the main androgens; testosterone – free and bound and dihydrotestosterone, as well as estradiol (estrogen) and the enzymes that initiate these conversions. The androgen to estrogen balance45-58 is increasingly being seen as a key component in reversing or slowing down the enlargement of the prostate and this area is where natural based phytotherapeutic agents such as Tongkat Ali provide an important complementary or alternative role to synthetic drugs for prostate enlargement.
It is rare for young men in their hormonal prime to suffer from hypo-androgenic erectile dysfunction. Similarly, BPH and consequent urinary complications are statistically rare in men below 35 years of age. Obviously high free (bioavailable) testosterone is a primary protecting influence. While the causes for why more testosterone is converted into DHT and estradiol with progressive aging is not fully understood, what is known is that the prostate gland itself is highly sensitive to these changes. The change from a positive ratio between high free testosterone to low DHT and estradiol to a negative ration of low free testosterone to high DHT and estradiol causes the prostate to enlarge, eventually leading to constriction of the urethra and difficulties in urination that can lead to progressive complications if untreated.
Herbal agents for the treatment of BPH such as Saw Palmetto are some of the most widely prescribed herbal medicines by the medical profession worldwide, especially in Europe. A primary motivating factor is that many clinical trials have shown comparable results to modern drugs with fewer effects64. Side effects from modern drug therapy in the treatment of BPH includes; loss of libido, ejaculation difficulties and lethargy. Unfortunately, herbs such as Saw Palmetto that work almost exclusively on reducing DHT often have a milder side effect of reducing libido and sexual function.
Evidence from trials on Eurycoma longifolia shows promise to correct the androgen profile to physiological norms for a healthy younger male. In this way it may act both to reduce prostatic enlargement or slow its progression, improve available testosterone and libido, reduce weight through its effects on metabolism and improve psychological well being. Note: This article has been adapted from a “novel use” research paper I submitted for review in 2008, apologies for it’s being a bit technical heavy.
Benign Prostatic Hyperplasia (BPH)
Benign prostatic hyperplasia is the non-malignant, uncontrolled growth of cells in the prostate gland. It is characterized by hyperplasia of prostatic stromal and epithelial cells, resulting in the formation of large, fairly discrete nodules in the periurethral region of the prostate. When sufficiently large, the nodules compress the urethral canal to cause partial, or sometimes virtually complete, obstruction of the urethra that interferes the normal flow of urine. The bladder no longer empties completely, creating an environment in which infections, bladder stones, and chronic prostatitis may develop. If left untreated, chronic obstruction can lead to the backup of urine into the ureters and compromise kidney function. Common symptoms of Benign Prostatic Hyperplasia are given below:
- Decrease in strength of the urinary stream and a decrease in the stream’s diameter
- Increased frequency in urinating during the day
- Need to urinate several times during the night (nocturia)
- Sensation of needing to urinate immediately (urgency)
- Straining to force urine out
- Dribbling urine or having difficulty stopping urination
- Having the feeling of still needing to urinate even after the stream has stopped
- Pain or a burning sensation during urination
- Complete retention of urine (because, in advanced BPH, an enlarged prostate can completely obstruct the passage of urine)
The prostate is a walnut-sized gland located beneath the bladder and in front of the rectum. A capsule of fibrous tissue called the prostate capsule surrounds it. The urethra passes through the prostate to the bladder neck. Prostate tissue produces prostate specific antigen (PSA) and prostatic acid phosphatase (PAP), an enzyme found in seminal fluid. Increased levels of PSA and PAP may suggest the presence of prostate cancer and are used as markers for early warning screening. PSA levels can be also elevated due to prostate infection, irritation or BPH.
BPH Incidence and Prevalence
It is difficult to establish incidence and prevalence of BPH because research groups often use different criteria to define the condition. Generally, most men in their lifetime will experience symptoms of the condition. General statistics for symptomatic BPH occurs in:
- 14% in men in their 40’s
- 24% of men in their 50’s
- 43% of men in their 60’s
- Growing to 80% of men who reach their 80’s
Prostate Enlargement Causes and Conventional Treatment
The cause of benign prostatic hyperplasia is believed to be associated with hormonal changes that occur as men age. Modern treatment for BPH thus focuses on drugs that inhibit the hormones that control prostate growth or that relaxes the smooth muscles inside the prostate gland. The testes produce the hormone testosterone, which can be metabolized into dihydrotestosterone (DHT) by the enzyme 5-alpha reductase. Drugs and nutrients that lower DHT by inhibiting 5-alpha reductase have been shown to reduce the size of the prostate gland and therefore reduce the symptoms of BPH. The unfortunate side effect of 5-alpha reductase drugs such as dutasteride and finasteride is a decline in androgen hormones leading to impotence, decreased libido, decreased semen quantity at ejaculation and occasional gynecomastia (fatty tissue breast development in men).
Testosterone is also converted by men into estradiol (estrogen) via the enzyme aromatase. As men age, aromatase levels increase, resulting in higher estrogen levels. Compared to younger males, older males have much more estradiol than free testosterone. These rising estrogen and declining androgen levels contribute to BPH and drugs and nutrients that reduce aromatase are now being used therapeutically.
Antihypertensive drugs called alpha-blockers act on the nervous system to relax arteries by inhibiting excitatory impulses to muscle cells. The smooth muscle cells in the prostate gland have alpha-receptors, so alpha-blockers are used to relax the muscle and reduce symptoms, and provide the most rapid symptom relief. The alpha-blockers used in the treatment of BPH include alfuzosin, doxazosin, tamsulosin, and terazosin. Many alpha-blockers can cause fatigue, rhinitis, hypotension, dizziness, abnormal ejaculation or impotence.
Surgery is widely used for treatment of BPH that is causing significant obstruction to urine flow. Surgery for BPH can be done through a transabdominal incision or through an endoscopic device inserted into the urethra (TURP). About 90 percent of all surgeries performed for BPH are TURP procedures. TURP is the standard against which other interventions are judged. The most common, unavoidable and permanent adverse effect of TURP is retrograde ejaculation. Inability to achieve erection is a less frequent adverse effect. Surgeries are associated with postoperative risks such as erectile dysfunction (4% to 10% incidence) and urinary incontinence (0.5% to 1.5%). The 5-year recurrence rate of BPH following surgery is 2 to 10%. The current clinical philosophy concerning BPH treatment is to postpone any form of surgery for as long as possible to avoid complications that may jeopardize the patient’s quality of life.
As a result of the potential for adverse effects from modern treatment many doctors today are researching alternatives in BPH treatment. However there has been little progress in the development of effective therapeutic agents in BPH despite the exponential growth in the consumer and clinical acceptance for herbal / phyto-pharmaceutical products targeting this condition, as seen in the sales of products based on the medicinal plant, Saw Palmetto. The reason for this growth is the current medical options concomitant side effects such as reduced libido and ability to achieve erection, an often associated problem in men suffering from the symptoms of BPH and one of the major factors causing men to seek natural options.
Tongkat Ali and the Androgen to Estrogen Ratio Theory of Benign Prostatic Hyperplasia
The use of Tongkat Ali as a natural treatment for prostate enlargement is based on the scientific premise that the hormonal etiology of BPH is not based on testosterone being converted to dehydrotestosterone (DHT) alone, but is also significantly influenced by estrogen. While estrogen is normally thought of as “the female hormone,” men produce estrogen throughout their lives by converting testosterone to estrogen using the enzyme aromatase. In youth, low amounts of estrogen are used to turn off the powerful cell-stimulating effects of testosterone. As estrogen levels increase with age, testosterone cell stimulation may be locked in the “off” position, leading to the common symptoms of “male andropause” such as reduced sexual arousal and sensation, and loss of libido. This helps explain why, as men age, testosterone levels decline (as higher aromatase levels convert testosterone to estrogen and estrogen blocks the receptor sites for testosterone), but prostate glands continue to enlarge as these rising estrogen and declining androgen levels are even more sharply defined in the prostate gland. Estrogen levels in prostate gland tissues rise even higher in men who have BPH and various researchers such as Kazuto Ito et al have shown the central role of Estradiol in prostate enlargement etiology:
“Androgens are widely acknowledged to be central to the pathogenesis of BPH. However, BPH increases in prevalence at the life stage during which plasma androgens are decreasing. The serum and intraprostatic estradiol (E2) to testosterone (T) ratio and the level of plasma sex hormone-binding globulin (SHBG) increase with age, and the resulting estrogen-dominant environment has long been suspected to be important for the pathogenesis of BPH.”
By limiting aromatase, or inhibiting the binding of estrogen to prostate cells, it is possible to reduce BPH. Modern drugs that work by blocking 5-alpha reductase without blocking aromatase turn the prostate into an “estrogen holding unit”. While being clinically effective in the short term in reducing prostate size, in the long-term they may aggravate the situation further by converting more testosterone into the strongest female hormone, estradiol. As such, DHT is not the sole cause of an enlarged prostate as the excess estrogen must also be addressed and this is one area where phytotherapy with herbs such as Tongkat Ali provide a more holistic approach to managing prostate growth in the ageing man.
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). Excess estrogen can increase the production of SHBG and block testosterone-receptor sites. This means there are two mechanisms by which excess estrogen interferes with both prostate and sexual function in aging males.
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. For aging men, it is desirable to suppress excess levels of SHBG and estrogen while boosting free testosterone to the level of a young man. Tongkat Ali offers are a natural way of modulating testosterone and estrogen levels in aging men. Estrogen levels of the average 54-year-old man are 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. 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.
Based on the multiple deleterious effects of excess estrogen in men therapies should be geared to reduce estrogen to a safe range. To determine if estrogen levels are too high, men are encouraged to have their blood tested for estradiol. If the blood test results show estradiol levels are greater than 30 pg/mL, men should consider adopting strategies to reduce the estrogen to testosterone levels.
What about Prostate Cancer?
The exact relationship between hormonal activity and prostate cancer is not fully understood. Testosterone is capable of either promoting prostate cancer cells or killing them. New evidence supports the theory that 17beta-estradiol is essential for initiating the growth of prostate cancer cells through the formation of telomeres. Free testosterone is considered to be protective, whereas its conversion to DHT promotes prostate cancer cell growth thus there are similarities between the etiology of BPH and prostate cancer. In a 2015 Malaysian study performed at the Faculty of Medicine, University Malaya, the researchers looked at the “Anti-Cancer Activities of a Standardized Quassinoids Composition from Eurycoma longifolia on LNCaP Human Prostate Cancer Cells” and observed that the Tongkat Ali extract inhibited human prostate cancer cells in the model used and reflected a high degree of safety worthy of further clinical study. This is a very promising area of further research.
Testosterone Replacement Therapy
Many men turn to synthetic androgen / testosterone replacement therapy in response to declining sexual function and the symptoms of male andropause, especially in the later years when they are most susceptible to having an underlying prostate condition or developing prostate disease. The major disadvantage with synthetic testosterone replacement is the common conversion into elevated levels of DHT and estradiol and increased potential to develop prostatic enlargement or prostate cancer if therapy is prolonged. Tongkat Ali supplementation has been shown to pose no such risk.
Tongkat Ali has been shown in multiple studies to positively influence androgen / testosterone levels within normal physiological ranges and restore positive androgen to estrogen ratios to those of a younger male and may thus act as a natural preventative and potential complementary treatment for prostate diseases. This new understanding of contributing factors to prostate enlargement also allows for men to play a greater role in taking responsibility for their own health and prostate disease prevention and make positive changes to their diet and lifestyle that supports their androgen to estrogen ratio.
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