|The Truth about Testosterone
Excerpted from "The Male Biological Clock" by Harry Fisch
Chapter 2: The Viagra Generation
After his wife was checked out for fertility problems and nothing was found, Jason went in for a semen analysis.
“My wife was checked out first because, of course, it’s always the woman’s problem, right?” he says. “But it turned out it was me…I had no sperm and a low testosterone level.”
When he came to see me, I confirmed his testicular failure, and also found a testicular tumor that required removal of that testicle. That left Jason with even less ability to make testosterone.
Eventually, he and his wife had two children using in vitro fertilization and a technique (discussed fully in Chapter 5) for finding and injecting sperm directly into a woman’s eggs.
But Jason’s story isn’t about his wife’s successful delivery of healthy twins. It’s about the effects of the testosterone therapy that he has used now for five years. In order to treat Jason’s extremely low testosterone levels, he began a course of testosterone injections every two weeks.
“I was about 100 pounds overweight,” Jason says. “I had been through every diet in the book, and the weight always came back. But the testosterone gave me a boost of energy that I never had before and for some reason, to this day, it allows me to control my appetite.”
At my suggestion, Jason began eating a sensible, healthy diet and, once he began to feel the testosterone kick in, he began to exercise for the first time in his life.
“When people would talk about their endorphins kicking in and getting that high from exercise, I didn’t know what they were talking about,” Jason says. “But now I do. With the testosterone, your body feels high, like you’ve got huge energy. You’re not sluggish, you bounce out of bed, get your shower, and you want to get to work. It’s that kind of feeling. Mind you, sometimes it’s still drudgery to go to the gym, but once I’m there, I really enjoy it, whereas before I could never even dream of exercising like this.”
Jason lost more than 90 pounds. He could buy clothes off the rack for the first time instead of having them custom made. He became much more confident in himself and says he feels years younger.
“Did it change my personality?” he asks. “Maybe. But I lost 90 pounds at the same time, so is it the weight loss or the testosterone? I don’t know.”
Jason is president of a thriving small business. He recalls a time after he’d lost his weight and bought new clothes. He had a meeting with a customer who was threatening to sever its ties with his business.
“They were saying they didn’t want to work with us, but I lost my weight and went into that meeting with my new look, Gucci suit, hip, no tie, open shirt, but in a conservative sort of way, and it was completely different,” he says. “I turned the whole thing around. And they’re one of our biggest accounts now. Because the perception of me changed. I was no longer this person who looked overweight and tired. All of a sudden I was a person with much more confidence, and I’m more gutsy, more full of myself.”
Like most men who use testosterone replacement therapy, Jason notices a distinctly heightened sex drive, particularly in the first few days after an injection. Although he says he’s never had a problem with his erections, now, at 44, he has noticed that his erections are more robust and he’s more easily aroused with testosterone.
Jason uses his testosterone responsibly. He gets blood tests every six months to monitor is liver function and prostate health. Thus far, he is much healthier now than before he began. His cholesterol levels and blood pressure improved and are excellent. And he experienced an unexpected benefit: relief from panic attacks.
“My panic attacks were so severe that I couldn’t get on a plane without getting drunk and having my pills,” he says. “It got to the point that I couldn’t even be in open places. But I haven’t had an attack now in four years. I’m in control now…and that’s the problem with panic…you feel like a you’re out of control. The shot makes me feel like I’m in control.”
Of course, testosterone therapy, particularly with injections, isn’t without drawbacks. Jason, who tried but just can’t give himself an injection, must make regular visits to get his shots, which can be a problem when he travels.
“It’s a hassle,” he says. “You know, getting to the nurse, ‘which cheek will it be this week?’ It’s a pain in the neck.”
He’s also not thrilled that he expects to continue this routine the rest of his life. Although new methods for delivering testosterone have been developed since Jason began his therapy, they don’t give him the levels he finds work best. Still, he says the hassle and discomfort are worth it.
“Heart disease runs in my family,” he says. “My dad died at 47. I was overweight and never would have lost that weight without the testosterone. Never. Now my cholesterol is incredible. I exercise hard at least three times a week. And isn’t it healthier and better to be like this than to have been going on the track I was going before, which I’m sure would have led to a serious problem?”
A Growing Problem and a Dangerous Fad
Between two and four million men in the US alone suffer from below-normal testosterone levels, a condition known as hypogonadism.
It’s a problem that gets progressively more common as men age, though it can also strike men at any age for a variety of reasons. Unfortunately, very few men with below-normal testosterone are getting the help they need. It’s estimated that only 5 percent of the millions of men with hypogonadism are currently being treated, despite a booming business in testosterone replacement therapies of many kinds. (Sales of prescription testosterone products have soared more than 500% since 1993.) This surge in the use of testosterone products may not be an entirely good thing. Testosterone replacement therapy is only appropriate and safe for men like Jason who have below-normal levels and who don’t have any medical conditions that could be made worse by testosterone, such as an enlarged prostate or evidence of prostate cancer. As we’ll see, use of testosterone by men with normal levels is very risky.
The symptoms of hypogonadism are often overlooked, because, in part, they are mistaken for ordinary signs of aging. Men with below-normal testosterone experience the following:
The enormous industry that has sprung up to capitalize on this problem, has contributed to a dangerous rise in the unregulated sale and use of testosterone supplements. Far too many men are obtaining quick-and-dirty prescriptions for testosterone, and abusing the hormone because it makes them feel temporarily younger and stronger. Myths and misunderstandings about testosterone abound. Here are the ones I hear most frequently:
- Low interest in sex
- Muscle weakness
- Small or soft testicles
- Erectile dysfunction
- Weight gain, particularly around the waist
- Reduced bone density
1. Testosterone improves fertility
False. As we will see in this chapter, testosterone, particularly at the levels commonly used by athletes for performance enhancement, can effectively sterilize a man and cause his testicles to shrink and become soft.
2. Being overweight has nothing to do with testosterone levels.
Wrong. Extra fat on the body acts like a sponge, taking testosterone out of the blood and reducing libido, energy, and other male-related characteristics. This is particularly true if the fat is carried around the belly or abdomen. Fat carried on the thighs or buttocks has less testosterone-draining effects.
3. Men can raise their testosterone levels by exercising vigorously.
The relationship between testosterone and exercise is complicated. Yes, moderate exercise can raise testosterone levels somewhat, but if exercise is extreme, testosterone levels can actually drop. It’s also true that low testosterone makes it harder to exercise, which can lead to a vicious cycle of inactivity and reduced hormone levels.
4. Male mid-life crises have nothing to do with testosterone.
I believe that many times when men say they are bored with their careers, their wives, or their general lot in life, they are actually suffering from low testosterone. I call this phenomenon “menoporche” because I’ve seen guys who think buying a hot new car will give them a shot of sex appeal or attractiveness, when, in fact, they would be much better off getting their testosterone level checked.
5. Testosterone supplements are safe because they have to be approved by the FDA.
Wrong. In fact, as of this writing, the government does not regulate the sale or use of products containing compounds that get converted into testosterone. Testosterone or testosterone precursors should only be used under a doctor’s supervision and testosterone levels should only be raised to normal levels.
6. Low testosterone causes depression.
True, but that’s just half the story. Most men don’t know that depression, or depressed mood, can lower their testosterone levels. Since many men don’t recognize signs of their own depression, or are reluctant to seek help treating depression, this is a significant problem for millions of men. Sometimes restoring testosterone levels can also alleviate symptoms of depression—and sometimes alleviating the depression with psychotherapy and/or antidepressant medications can raise testosterone levels.
7. Erection-enhancing medications such as Viagra work whether a man has normal testosterone levels or not.
In fact, studies show that erection-enhancing medications work best in men with testosterone levels in the normal range. Testosterone provides the necessary urge to have sex that erection-enhancing drugs cannot provide.
8. Testosterone therapy is really just a form of cosmetic pharmacology—it’s just something middle-aged men try to make themselves feel young.
Wrong. Testosterone replacement for men of any age who have below-normal levels is a valid medical treatment for a condition with clear potential to degrade overall health and well-being. Failure to treat hypogonadism puts men at higher risk for frailty, osteoporosis, heart disease, and, perhaps, Alzheimer disease.
9. Low testosterone is only a problem for old men.
False. Certainly the older you are, the more likely you are to have low testosterone, but this condition can affect any man, even teenagers. Conditions such as varicoceles, undescended testicles, and certain genetic problems can cause below-normal testosterone levels which need to be diagnosed and corrected as quickly as possible.
10. The only way to boost testosterone levels is with shots.
Several options are now available for testosterone replacement therapy, some of which work by coaxing the body to increase testosterone levels naturally rather than by dumping testosterone directly into the bloodstream one way or the other.
Being Smart about Testosterone
Testosterone clearly plays a major role in men’s health and fertility—but achieving healthy levels must be done the right way. As with anything, knowledge is power, and to reap the benefits of testosterone therapy you must learn a little about what testosterone is, how it works, and what can cause levels to sink below normal.
Low testosterone (hypogonadism) can be caused by many factors, all of which play out against the normal steady decline in testosterone levels with age. Tumors on the pituitary gland (which controls testosterone production in the testicles), problems with the testicles themselves, injury, infections, and being overweight can all cause testosterone levels to drop below normal. Excess body fat does this because testosterone is normally broken down in the body’s fat cells, hence if you have a lot of fat, your body breaks down testosterone extra-quickly, leading to a deficiency. And, as mentioned above, abdominal or “belly” fat has a greater capacity to convert testosterone to estrogen than other types of fat.
Another risk factor for hypogonadism that has only recently come to light is diabetes. A strong relationship has been discovered between impaired glucose tolerance, which is a cardinal feature of diabetes, and low testosterone levels. It appears that the high blood sugar levels and/or low insulin levels characteristic of diabetes harm the cells in the testicles that are responsible for making testosterone. A very recent study of 221 middle-aged men confirmed this finding: the men most likely to be diabetic also had the lowest testosterone levels.
The reverse may also occur: low testosterone levels may decrease insulin sensitivity to lower muscle mass, thereby making diabetes worse. Because diabetes, particularly adult-onset diabetes, has been steadily rising as a health problem in most developed countries, the prevalence of hypogonadism associated with this disorder will likely rise as well in coming years. We’ve already seen a rise in a condition known as metabolic syndrome which is a pre-diabetic state among men with low testosterone levels, abnormal lipid profiles, insulin insensitivity, and weight gain around their middles. In fact, one of the clearest signs of both low testosterone and a tendency toward diabetes is abdominal fat. If your waist is larger than 40 inches and you tend to carry excess wait in your middle, as opposed to your thighs or buttocks, you may be at risk for both conditions.
Why Testosterone Replacement Isn’t for Everyone
Many body tissues are sensitive to testosterone including muscles, bones, the brain, skin, testicles, blood, and the prostate gland. This means that any alterations in testosterone levels will have very wide-ranging effects. For men with truly inadequate testosterone, increasing testosterone may be a boon or, at least, the risks are outweighed by the potential benefits of therapy. For men with normal testosterone levels though, increasing testosterone is hazardous.
The most familiar risk from boosting testosterone is raising the risk of prostate cancer or prostate enlargement. In truth, the latest research can’t pin down this risk very well because the needed long-term controlled clinical trials have not been done. In a very real sense, medicine is at the same stage with testosterone replacement therapy (TRT) in men as it was with hormone replacement therapy (HRT) for women 20 years ago. That should be a red flag for everyone involved in the current debates over TRT. When hormone replacement therapy was first used with women it was considered very safe and to have many positive attributes, such as being good for the heart and bones. Early, short-term, and preliminary studies seemed to bear this out. But when long-term studies were eventually done, it became clear that HRT not only does increase the risk of certain cancers, it is not beneficial for the heart. Because of all this, other treatments are now being used for alleviating menopause symptoms, increasing bone density, and ensuring cardiovascular health.
The suggestions that testosterone replacement therapy may increase the risk of prostate problems comes from several related lines of evidence. First of all, we know that the prostate is very sensitive to testosterone levels—testosterone causes prostate growth while eliminating testosterone shrinks the prostate. In fact, various methods of reducing testosterone are used to treat both prostate cancer and benign prostate enlargement. Studies also clearly demonstrate that the prostate grows following testosterone supplementation. Prostate enlargement, by itself, is not necessarily a problem—it’s only when that growth causes pain or other problems, such as difficulty urinating or an inability to fully empty the bladder, that it needs to be treated. The studies to date fail to find a correlation between testosterone replacement therapy and any annoying urinary symptoms that sometimes—but not always—accompany enlargement.
A less well-known effect of boosting testosterone is an increase in the numbers of oxygen-carrying red blood cells. Again, for men suffering from anemia or lack of energy, this effect may be welcome and can increase their energy and endurance. But adding blood cells also makes the blood thicker and more prone to clogging in tiny vessels, hence it can theoretically increase the risk for a variety of cardiovascular problems such as heart attack and stroke.
One original concern about the safety of testosterone therapy has dissipated in recent years. Early studies suggested that testosterone replacement therapy hurt the balance of high-density lipoprotein (the so-called “good” cholesterol) to low-density lipoprotein (the “bad” cholesterol). But more recent studies suggest that, as long as testosterone levels are held within normal limits, blood lipid profiles are unaffected or may even improve.
Testosterone replacement therapy can sometimes cause other, less potentially serious effects such as increased acne, increased snoring and sleep apnea (sudden waking from a transitory interruption of breathing), softening of the testicles, and breast tenderness or enlargement. It may also speed up male pattern baldness, though this effect has not been rigorously documented.
Whether fertility is affected by testosterone replacement depends on many factors. As a general rule, male infertility is only very seldom caused by low testosterone and boosting testosterone artificially usually reduces fertility. In fact, relatively high levels of testosterone act as a fairly effective form of birth control.
This fact is not widely known. Thousands of men are using testosterone supplements that hurt their fertility.
Steve was one of those guys. When Steve came to see me, he was wearing a tight-fitting polo shirt that revealed a heavily-muscled torso. He was tan and gave the outward appearance of excellent health. But he had practically no sperm in his semen and his testicles were small and soft. My suspicion that he was using a supplement that boosted his testosterone was confirmed when his blood test results came back: his testosterone level was three times higher than normal.
Here’s how all that extra testosterone had, essentially, crippled his reproductive system.
A man’s body (actually certain key parts of his brain) constantly monitors the level of testosterone in his blood. When levels fall, the brain sends signals to the testicles to boost production, and when levels rise, the brain tells the testicles to shut down. Adding extra testosterone, in other words, tricks the brain and causes it to send signals that not only shut down testosterone production, but sperm production as well. The result are smaller, softer testicles, and infertility.
When I explained this to Steve he was shocked. He had no idea. He agreed to stop taking the supplements he was using and I prescribed a medication to help kick-start his body’s natural testosterone production machinery. His sperm count began to come back in three months and by six months it was normal. Several months after that Steve’s wife became pregnant. Their baby girl was born two years ago.
Steve’s case illustrates the potential hazards of testosterone on fertility. We’ll talk more about over-the-counter products later, but here I want to stress that if you are trying to have a baby, do not use any nutritional or natural supplements that claim they will boost muscle mass, increase your metabolism, or promote growth. All such products can hurt your fertility, ejaculatory function, or erectile function.
In certain cases, however, judicious manipulation of testosterone can improve sperm counts, motility, and morphology. This is best done, in my opinion, by using medications that indirectly boost the body’s production of testosterone rather than using testosterone replacement itself. (See the section on alternatives to testosterone later in this chapter.)
The bottom line is that testosterone replacement therapy is a real, potentially valuable treatment for men with below-normal levels, but it poses equally real risks for men with normal levels. Any man considering testosterone replacement therapy of any kind must have his prostate checked beforehand, both with a digital rectal exam and a blood test of levels of prostate-specific antigen (PSA) which is a marker of prostate health. Any man already using testosterone replacement therapy should have these tests every six months.
Types of Testosterone Replacement Therapy
Testosterone molecules are rapidly destroyed in the acidic conditions of the stomach and are poorly absorbed. When taken orally, testosterone also impacts the liver, sometimes dangerously so. For these reasons, testosterone pills, though available, are not recommended by most doctors in this country. The safest ways to deliver testosterone avoid the stomach, entering instead through the skin with gels or patches or directly into the blood via injections. These approaches differ in how well they create an even, natural level of testosterone. Injections, which are taken every two to three weeks, produce a very spiky pattern of testosterone levels.
This pattern results in above-normal levels immediately after the injection and below-normal levels in the days before the next injection. Injections come in a variety of doses and are usually given every two to three weeks. In addition to the erratic testosterone levels they produce, injections are somewhat painful and involve frequent trips to a doctor’s office if a man is not willing or able to inject himself. Side effects from testosterone injections are relatively uncommon, but can include acne or oily skin, sleep apnea (temporary cessation of breathing during sleep which prompts waking), breast swelling, and softening or shrinking of the testicles.
Patch and gel forms of testosterone, by contrast, produce much more steady and even levels of testosterone as you can see in this graph.
The gel form of testosterone is the newest and, as of this writing, the most popular way to delivery testosterone. It is also the best treatment for maintaining an even hormone level and reducing undesirable side effects such as those just mentioned above for injections with the addition of possible skin irritation or inadvertant transfer of testosterone to others who rub against the gel. Sold under the brand name AndroGel, this preparation is a clear, quick-drying gel containing 1% testosterone. Applied daily on the skin of the upper arm, shoulders, or abdomen it begins releasing testosterone through the skin in about 30 minutes.
Two types of testosterone patches are available, one of which applied to the scrotum, the other to the back, stomach, thighs, or upper arms. The patches share the advantage of the gel in delivering a steady, even dose of testosterone to the body, though they are significantly more likely to cause skin irritation or a rash.
An Alternative to Testosterone
Clomiphene citrate, marketed in pill form as Clomid or Serophene, has long been used for female infertility to spur the ovaries to produce mature eggs. It works by stimulating a part of the brain (the pituitary gland) that controls production of two hormones key to reproductive health: follicle stimulating hormone (FSH) and luteinizing hormone (LH). Both hormones are also vital to men. FSH stimulates sperm production in the testicles, and LH stimulates testosterone production. So it made sense to a number of urologists who treat male infertility, including me, to try clomiphene citrate in men. A number of studies have now conclusively demonstrated that this strategy works—and it does so by working with the body rather than dumping extra testosterone on it from outside. The result? A much-reduced risk of impaired fertility. Indeed, judicious use of clomiphene citrate can stimulate sperm production and sperm quality in men with reduced testicular function.
For example, Murray came to me because he and his wife were having difficulty getting pregnant and a semen analysis showed he had a low sperm count. When I examined him I found a varicocele (pronounced “VAYR-uh-ko-seal”), which is a set of distended veins in the testicles. Varicoceles are a common cause of impaired fertility because the extra blood in the veins around a testicle warms the testicle, which hurts the cells that produce sperm. (See Chapter 4 for more information about diagnosing and treating varicoceles.)
After surgically repairing the varicocele, I prescribed Clomid to boost Murray’s testosterone levels, which, in turn, usually helps sperm production. About six months after the surgery, Murray’s wife got pregnant. Unfortunately his wife had a miscarriage, but she got pregnant again soon after and that child was carried to term. Their little boy was born ten weeks ago as of this writing.
The Clomid raised Murray’s testosterone and he liked how he felt on it. An avid runner, he noticed significant changes in his strength and energy.
“I felt more energized, and stronger,” he says. “I noticed that I could do more pull-ups, and my running times kept going down. I was running with more motivation and strength.”
Murray didn’t notice any differences in his mood or sex drive. The only side effects he noticed were some insomnia in the initial weeks of the treatment and a tendency to sweat more easily, particularly on his palms. He liked the feeling the Clomid gave him so much he decided to stay on it after his wife got pregnant.
Murray’s story is backed up by solid research. Here’s an example of the kind of data we’ve found in our studies of clomiphene citrate:
A group of men with below-normal levels of testosterone were studied. Their average testosterone level at the start of the study was about 250 ng/dl. We then randomly assigned the men to get either clomiphene or a placebo (dummy pill). After two months, the testosterone levels in the clomiphene group had more than doubled, while the levels in the placebo group had risen only modestly and were not statistically significant. 75% of these men also reported increased libidos.
It’s important to point out that some of the warnings and caveats about testosterone mentioned above also apply to clomiphene. This treatment should only be used by men with below-normal testosterone and only for men who are not at risk for prostate cancer, cardiovascular problems, stroke, or breast cancer. Men using clomiphene therapy still need to be regularly monitored for prostate problems with both a PSA test and digital rectal exams. These are sensible cautions, since we’re still in the early stages of research on this medication in men.
I believe using clomiphene is an excellent way to raise the body’s testosterone levels—particularly in men using it to treat infertility. Other drugs similar to clomiphene are being developed that may provide similar benefits with, perhaps, lower risks (though clomiphene is, relatively speaking, a very safe drug). These drugs are called selective estrogen receptor modulators, or SERMs, and, like clomiphene, they work by stimulating a man’s body to make more testosterone. Future research into these drugs and others like them may provide a new generation of medications to safely and effectively increase testosterone levels without the need for direct testosterone replacement therapy.
As just mentioned, testosterone isn’t the only important hormone involved in male sexual health. The regulation of both testosterone levels and sperm production starts with a master-control gland in the brain called the hypothalamus. The hypothalamus secretes gonadotropin releasing hormone (GnRH) which travels to the nearby pituitary gland and stimulates that gland to make two other key hormones: luteinizing hormone (LH), which controls testosterone production, and follicle-stimulating hormone (FSH), which stimulates sperm production.
Sometimes the hypothalamus is either damaged by a tumor, radiation, or unknown reasons and doesn’t produce enough GnRH—a condition with the tongue twisting name hypothalamic-hypogonadotropic hypogonadism. With the master control switched off, the pituitary never gets the signal to produce its hormones and the testicles remain in a juvenile state, not producing either testosterone or sperm. Treatment with a combination of trice-weekly injections with a compound called human chorionic gonadotropin, coupled with another medication called Pergonal to boost sperm production frequently restores normal functioning and fertility. GnRH itself can also be delivered via a portable infusion pump that delivers the hormone directly to the blood every two hours.
The pituitary gland is also subject to failure, most commonly from non-cancerous tumors. In such cases, LH production might fail (resulting in a loss of testosterone), FSH production might fail (resulting in reduced sperm counts), or both will fail, producing a loss of both sexual desire and fertility. The most common treatment for cases of low LH or FSH is clomiphene citrate, which we discussed in detail earlier.
Another pituitary hormone, prolactin, is also rarely involved in a problem. Prolactin is normally found in very low levels in men, but high levels in women, where it stimulates milk production in the breasts. Pituitary tumors or genetic defects in the pituitary can send prolactin levels soaring, producing a range of symptoms such as low sperm counts, loss of sexual desire, trouble reaching orgasm, and growing breast tissue around the nipples. High prolactin levels in a man also disrupt the actions of other reproductive hormones which, in turn, further hurt fertility. Treatment with the medication bromocriptine often succeeds in restoring normal hormone levels and fertility. It can also shrink pituitary tumors. Side effects of the drug include fatigue in the early stages of treatment, headache, nausea, and dizziness.
Here are the normal levels for all the important hormones related to male sexuality:
||300 – 1100 ng/dl
||0.8 – 9 mIU/ml (milli International Units per milliliter)
||0.5 – 10 mIU/ml
||0.1 – 15.2 ng/dl
The specific pattern of abnormalities (if any) among these hormones can help determine if a problem is in the testicles, the pituitary gland, or other parts of the brain or body.
In the quest for bigger muscles, improved athletic performance, or enhanced sexuality, hundreds of thousands of men have turned to over-the-counter compounds that purport to boost testosterone. Some of these products are actually fake versions of FDA-approved products such as testosterone patches or gels. Others contain compounds that are converted to testosterone in the body. The most common of these testosterone precursors are dehydroepiandrosterone (DHEA) and androstenedione. The latter gained notoriety in the late 1990s when baseball slugger Mark McGwire disclosed that he routinely used “andros” (though he didn’t say how much he used.)
Scientific studies of both precursors using recommended doses of from 100 mg. to 300 mg a day have failed to prove any of the sometimes outlandish claims made by manufacturers. Nonetheless, many anecdotal reports suggest that some men do, indeed, see results from these compounds, such as added strength and bigger muscles. The explanation for the discrepancy is undoubtedly that many men are using doses far higher than those suggested by the manufacturers and higher than those used in the scientific studies.
The bottom line: precursor compounds do end up as testosterone and, thus, all of the risks noted above apply to them. It doesn’t matter that the testosterone is produced by the body in this case—the extra testosterone will impair fertility, bring a man’s natural testosterone production to a screeching halt, and increase his risk for prostate cancer, heart attack, and stroke.
The safest approach is simply to avoid all nutritional supplements if you are trying to have a baby because many contain hormones or hormone precursors that can hurt fertility and ingredients are often labeled in deceptive ways. The array of products now available is so huge and the number of brand names so large that a comprehensive list isn’t feasible. In general, however, any supplement containing the following ingredients or which include the following words should be suspect:
Men should also avoid any products that claim to boost energy because they often contain a stimulating compound such as ephedra, caffeine, and analogs of amphetamine. Such stimulants can impair ejaculatory function and reduce the amount of semen ejaculated at orgasm. Compounds containing human growth hormone (HGH) or claiming to boost growth hormone should be avoided as well, by the way. Research on the potential effects of such products on fertility has not been done, but we do know that such hormones stimulate all growth in the body—including the growth of both cancerous and non-cancerous tumors.
- dehydroepiandrosterone (DHEA)
In summary, abnormally low testosterone—one of the cardinal signals of an advanced biological clock—can safely be restored for the millions of men suffering from hypogonadism. Men on testosterone replacement therapy can realistically look forward to renewed interest in sex, improved erectile function, and (if they also exercise) larger and stronger muscles and reduced fat. The erosion of sexual performance wrought by the clock can thus be remedied quite effectively. Always bear in mind that the use of testosterone or any of the many products containing testosterone precursors by men with normal levels can be dangerous and will likely hurt their fertility. Before beginning testosterone replacement therapy, men should attend to all of the factors to improve their overall health and fitness.
- Rhoden EL, Morgentaler A. Risks of Testosterone-Replacement Therapy and Recommendations for Monitoring. New England Journal of Medicine. 2004;350:482-492.
- Bhasin S, Buckwalter JG. Testosterone supplementation in older men: a rational idea whose time has not yet come. Journal of Andrology. 2001;22:718-731.
- Tsai EC, Matsumoto AM, Fujimoto WY, Boyko EJ. Association of Bioavailable, Free, and Total Testosterone With Insulin Resistance. Diabetes Care. 2004;27:861-868.
- Rhoden EL, Morgentaler A. Risks of Testosterone-Replacement Therapy and Recommendations for Monitoring. New England Journal of Medicine. 2004;350:482-492.
- Guay et al. Journal of Clinical Endocrinology and Metabolism. 1995.
- Segal SJ and Mastroianni L. Hormone Use in Menopause and Male Andropause. Oxford University Press, New York, NY. 2003, p. 116-118