Life Extension Magazine February 2004
Testosterone Attacked by the Media
|Life Extension Reveals the Facts...|
On November 12, 2003, the Institute of Medicine, a government-supported nonprofit organization, issued a news release announcing the publication of a book entitled Testosterone and Aging.
The news release stated that after careful evaluation of the pros and cons of conducting a large-scale clinical study of testosterone therapy to treat age-related conditions in men, an expert committee recommended going forward with smaller-scale trials.
Concerns about safety and efficacy were clearly spelled out, as in the following excerpt from the Institute of Medicine news release:
“The committee found no compelling evidence of major adverse side effects resulting from testosterone therapy, but the evidence is inadequate to document safety.”
In response to this news release, the news media attacked the use of testosterone therapy as being dangerous and useless. The following excerpt is from an Associated Press story that was widely circulated throughout the US:
“Tens of thousands of aging men are trying testosterone shots, patches, and gel in hopes of regaining youthful vigor and virility. A new book uncovers little evidence it works— or that the therapy is even safe—but recommends careful study to find out.”
In addition, newspapers and other media organizations around the country ran the following headlines on November 12-13 that blatantly distorted the Institute of Medicine book:
The media misrepresented findings about the risks and benefits of testosterone therapy. In this article, Life Extension reviews and critiques the new Testosterone and Aging book and the media’s inaccurate portrayal of what the book says.
We have found that a major flaw with these kinds of government-sponsored publications is that they are written by “committees of experts” that appear to lack a comprehensive understanding and the clinical experience of using testosterone to treat age-related disorders. For instance, the committee cites studies where testosterone did not produce long-term benefits. Anti-aging doctors, on the other hand, have long known that most men taking testosterone also need aromatase-inhibitors to block the conversion of testosterone to estrogen. Too much estrogen in a man nullifies the beneficial effects of testosterone. Excess estrogen also contributes to a number of serious disorders ranging from heart disease to prostate cancer.
These committees also fail to realize the critical importance of individualizing a testosterone replacement program. Life Extension’s testosterone protocol, for example, mandates blood testing to ascertain how much testosterone, aromatase inhibitor, and/or 5-alpha reductase blocker are needed based on a person’s individual health profile and needs. The studies reviewed and proposed by the Institute of Medicine give groups of aged men the same amounts of testosterone without factoring in critical individual requirements.
In reviewing safety data, the Institute of Medicine’s committees bring up every side effect that could possibly occur, but overlook the blood-testing protocols used by most anti-aging physicians to guard against these problems. Despite its concern about possible side effects, the Institute of Medicine recommends initiating clinical trials based on “preliminary evidence” that testosterone therapy may “improve strength, sexual function, cognitive function, and general well-being” in aging men. Left out of the news release is evidence that testosterone therapy also protects against osteoporosis, anemia, and heart disease.
The Institute of Medicine’s proposed initial clinical trials would ascertain the efficacy of testosterone therapy over a one-to two-year period. Once efficacy is established, much longer trials would be needed to ascertain safety.
While the Life Extension Foundation endorses more human clinical trials, the concern is that the study design may be so badly flawed that the results will not reflect the benefits attainable if proper male hormone modulation therapy is administered. Proper testosterone therapy involves the use of drugs to block excess estrogen and DHT (dihydrotestosterone), in addition to individualizing the dose of testosterone. As this will be a government-funded study, the needs of the “individual” are seldom factored in.
It is becoming increasingly clear that government studies are designed for the masses, not for the individual who wants to follow a scientifically designed program to forestall the degenerative effects of aging. In this article, you will see why the government is not the appropriate body to determine the risk-benefit ratio of novel anti-aging therapies, including testosterone replacement.
To fully understand the vital importance of optimal testosterone levels to men of all ages, it is worthwhile to spend a few minutes on the genesis of this quintessential marker of manhood.
Testosterone is a substance that has been intimately tied throughout the ages to a man’s virility and sexuality. While the testicles are the organs in a man’s body that secrete testosterone, production of this vital male hormone actually begins with a cascade of biological events that occur in the brain. Testosterone synthesis begins when the brain’s pituitary gland secretes lutenizing hormone, which then prompts the testicles to produce testosterone via the Leydig cells. It has been estimated that a man begins life with 700 million Leydig cells and begins to lose 6 million of those cells each year after his twentieth birthday.1
After testosterone is secreted into the bloodstream via the Leydig cells, it can follow several different paths. Some testosterone attaches with another biochemical known as sex hormone binding globulin, or SHBG. Testosterone not bound up with SHBG is known as free testosterone, and it is in this form that testosterone can exert its powerful effects on the human body. Testosterone also can be converted via enzymatic pathways into different hormones. Through the actions of the 5-alpha reductase, an enzyme found in multiple tissues but concentrated in the prostate gland, testosterone can be converted into dihydrotestosterone, or DHT. Testosterone also can be converted to estrogen via the actions of aromatase, an enzyme found in skin, fat, bone, and brain cells.
Estrogen—which is not just one hormone but several related compounds with very similar biological activity—only recently was discovered to be important in many physiological functions in men, including maintenance of bone mass and cognitive function.2
While some estrogen is essential to men’s health, too much of it can be quite harmful, especially when in the form of 16-alpha-hydroxyestrone. This chemical, a breakdown product of estrogen metabolism, has high estrogenic activity and has been implicated for its carcinogenic activity. Another estrogen metabolite, 2-hydroxyestrone, is believed to be much less harmful, and a ratio tilting toward the 2-hydroxyestrone is thought to be beneficial.
Testosterone Decline: Andropause
Total testosterone levels peak in a man at approximately age 30; by age 40, 5% of men are thought have low testosterone levels, and by age 70, that figure goes up to at least 40-50%.4 In addition to the absolute change in total testosterone levels, changes also are seen in the ratio of free testosterone to testosterone bound to SHBG. In many aging men, and certainly in those who are obese, free testosterone levels drop significantly as SHBG levels increase and “bind up” the remaining free testosterone.