Life Extension Magazine February 2004
Testosterone Attacked by the Media
|Life Extension Reveals the Facts...|
Does Testosterone Cause Prostate Cancer?
“population-based studies clearly document the relationship between aging and both increases in prostate cancer incidence rates and decreases in circulating [and free] testosterone levels. While this relationship does not equal causality, the findings do raise intriguing hypotheses regarding the influence of testosterone on inhibiting prostate carcino-genesis.”
Estrogen’s Role in Prostate Cancer
The Institute of Medicine’s Recommendations
“Endogenous testosterone levels clearly decline with aging, but it is not clear if lower levels of serum testosterone affect health outcomes in older men.”
Following this remarkable statement, the authors then conclude on p. 100:
“A systematic review of the medical literature on testosterone therapy, particularly placebo-controlled trials in older men, demonstrated that there is not clear evidence for any of the health outcomes examined.”
Given the mind-set exemplified by the previous statement, the Institute of Medicine’s recommendations and conclusions should come as no surprise. On pp. 117-167, the authors detail the committee’s key conclusions, considerations, and recommendations, based on their rather skeptical view of testosterone’s effect on the aging process in men and the use of testosterone supplementation. Their first recommendation is to conduct trials of testosterone supplementation only in older men—those aged 65 and above—and to focus on testosterone supplementation as a therapeutic intervention rather than a preventive measure. The problem here is that it is well established—and even acknowledged by the Institute of Medicine—that in most men, testosterone levels begin falling while they are in their forties. While it is certainly worthwhile to try to treat debilitating symptoms of any disease or pathological process, be it an infection or aging, it is almost always better to try to prevent symptoms rather than treat them once they are in place.
The recommendations continue with the idea of starting research trials with studies to determine whether there is any benefit to testosterone supplementation, and if so, then conducting longer-term trials. The glaring problem with these recommendations is that a significant number of clinical trials already have been conducted—many referenced by the Institute of Medicine—that prove the efficacy of testosterone supplementation for treating a variety of andropause-related symptoms. In addition, longer-term studies of up to three years already have been conducted and have established the usefulness of testosterone supplementation in both middle-aged and elderly men. In the journal The Aging Male, researchers recently presented the findings of a three-year study of 122 men, aged 19 to 67, who were treated with testosterone gel.19 As with numerous earlier studies, the study authors found that long-term treatment with testosterone supplementation causes a statistically significant improvement in bone mineral mass and sexual desire, an increase in muscle mass, and a decrease in fat mass.
The Institute of Medicine’s final recommendation concerns the safety of the men participating in the testosterone supplementation trial. To accomplish this, the committee would set up strict exclusion criteria, mandate careful monitoring of markers of prostate function such as PSA (prostate specific antigen) levels, and seek to ascertain whether long-term testosterone supplementation can cause a rise in prostate cancer. While these recommendations are commendable, significant omissions also are obvious, such as failing to include monitoring of SHBG and estrogen levels along with the use of estrogen blockers (aromatase-inhibitors).
It is puzzling, at the very least, why the Institute of Medicine fails to even mention the significant effect of rising estrogen levels on prostate cancer when a substantial amount of well-researched literature has been published on this very subject.
Conclusions of the Institute of Medicine
“The trials that have been conducted do not show definitively that there are benefits of testosterone therapy for older men…the committee recommends short-term efficacy trials to determine if there are benefits of testosterone therapy in older men.”
Apparently, at the cost of the health and possibly lives of many thousands of middle-aged and elderly men, the Institute of Medicine committee has decided that yet another trial of testosterone supplements should be conducted, a trial that will take years and be funded by taxpayers, while those very same taxpayers are suffering from the very real, and often very debilitating symptoms, of andropause-induced testosterone deficiency.
Instead of reading the Institute of Medicine’s book, the media instead chose to malign the multiple benefits of testosterone replacement and exaggerate its potential side effects. Testosterone and Aging cites numerous clinical studies showing significant anti-aging effects, but the media reported only the disparaging conclusions made by certain committee members that had little or no basis in fact.
Unlike the mainstream media, we actually read the book, which provides solid scientific evidence that aging men should seek to maintain youthful testosterone levels.
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