Life Extension Magazine November 2008
As We See It
Dangers of Excess Estrogen In the Aging Male
By William Faloon
How Excess Estrogen Levels Occur in Aging Men
In males, the main biologically active estrogen is estradiol. The primary source of estradiol in men is from the conversion (aromatization) of testosterone. As men age, the production of androgens from the adrenals and gonads is decreased. The aromatization of testosterone to estradiol is often maintained, but due to a variety of factors, more testosterone is aromatized in fatty tissues, causing a further imbalance of the ratio of testosterone to estrogen, i.e. too much estradiol and not enough testosterone. The result is a deficiency of beneficial testosterone and an excess amount of estradiol.34
As men age, the amount of testosterone produced in the testes diminishes greatly. Yet estradiol levels remain persistently high. The reason for this is increasing aromatase activity along with age-associated fat mass, especially in the belly.5 Estradiol levels correlate significantly to body fat mass and more specifically to subcutaneous abdominal fat. The epidemic of abdominal obesity observed in aging men is associated with a constellation of degenerative disorders, including heart disease, diabetes, and cancer.9,35-38
Subcutaneous abdominal fat acts as a secretory gland, often producing and emitting excessive levels of estradiol into an aging man’s blood.39 One’s waist circumference is a highly accurate prognostic measurement of future disease risk, with excess estradiol secretion being at least one of the deadly mechanisms associated with the difficult-to-resolve problem of having too much abdominal fat.5,40
Symptoms of excess estrogen in aging men include the development of breasts, having too much abdominal weight, feeling tired, suffering loss of muscle mass, and having emotional disturbances. Many of these symptoms correspond to testosterone deficiency as well.41
Don’t Lower Your Estrogen Too Much!
When reviewing the studies about the multiple pathological effects of excess estrogen in aging men, it may be tempting to take high doses of an aromatase-inhibiting drug (like Arimidex®) to slash estrogen levels as low as possible. Don’t do this, as men need estrogen to maintain bone density, cognitive function, and even to maintain the inner lining of the arterial wall (the endothelium).42
Most Life Extension members know that too little cholesterol (below 150 mg/dL) can be more dangerous than too much cholesterol (levels over 200 mg/dL). The same may hold true for estrogen. We have recommended that ideal ranges for estradiol for most aging men are between 20 and 30 pg/mL of blood. Below 18 pg/mL increases osteoporosis risk, while levels greater than 30 pg/mL increase heart attack and stroke incidence.
The availability of low-cost blood tests enables aging men to optimize their estradiol levels using natural approaches and/or prescription drugs.
Estrogen and Men’s Bones
Osteoporosis is not just a risk for aging women. Men also suffer crippling fractures caused by loss of bone mineral density. When aged men suffer a bone fracture, their risk of dying is significantly higher than women.43,44
In a study published two years ago, doctors analyzed blood levels in three groups of men for estradiol only, testosterone only, and estradiol and testosterone together. In men with low estradiol (2.0-18.1 pg/mL of blood), hip fractures were more than three times higher compared with men who had estradiol levels of 18.2-34.2 pg/mL.45
Men with estradiol levels greater than 34.3 pg/mL had a slightly higher risk of hip fracture compared with those in the range of 18.2-34.2 pg/mL. This study helps confirm Life Extension’s recommended range for estrogen levels in aging men.
Interestingly, this study also showed in the group of men whose blood was measured for estradiol and testosterone, those who were low in both these hormones suffered a startling 6.5 times greater incidence of hip fractures. The authors of this study concluded, “men with low estradiol levels are at an increased risk for future hip fracture. Men with both low estradiol and low testosterone levels seem to be at greatest risk for hip fracture.”45
With the voluminous amount of scientific studies being published today, contradictions inevitably arise, and this is not always due to study design flaws.
For the past decade, Life Extension has reported on dozens of studies showing that higher testosterone levels significantly reduce a man’s risk of cardiovascular disease. In fact, we just did a comprehensive database search and identified a total of 50 studies that document the protective effects of testosterone against cardiovascular disease in men.
A study published two years ago, however, contradicts this. This study showed greater incidences of heart attacks in men with higher testosterone and lower heart attack risks in older men with higher estradiol. (In younger men, estradiol level had no impact on heart attack incidence in this study.) The authors of the study admitted a limitation to the study was only measuring baseline levels of hormones. This study nonetheless was used at the anti-aging conference to proclaim that estradiol protects against heart attack.46
There are scientific studies that demonstrate estrogen’s potential beneficial effects to a man’s vascular system. These protective mechanisms, however, have to be weighed against pathological damage the very same estrogen can induce.
As I mentioned earlier, despite the documented dangers of excess estrogen, levels that are too low also present risks, not only to bone,45,47-49 but to the vascular system as well.46,50,51 If a man were to intentionally lower his estradiol too much, he could very well suffer vascular disease because estrogen is vital to proper endothelial function.52,53
This is why it is so important for aging men to have annual blood tests. If estrogen is too low (below 18-20 pg/mL), or too high (above 30 pg/mL), corrective action should be taken.
How to Reduce Excess Estrogen
In aging men, a large percentage of estradiol is synthesized in abdominal adipose (fat) tissues.42 Reducing waist circumference confers huge health benefits, one being a lowering of estradiol levels.
One of the most effective ways for men to reduce belly fat is to restore their free testosterone to youthful ranges. Nutrients that inhibit the aromatase enzyme can help boost testosterone levels by preventing its conversion (aromatization) into estradiol.
As men grow older, however, their testicular testosterone production declines precipitously. This means that inhibiting aromatase might not sufficiently maintain testosterone levels because not enough is being produced internally. Fortunately, low-cost compounded testosterone creams are available that can be rubbed on the skin for absorption into the bloodstream.
For men with excess aromatase activity, this topically absorbed testosterone might convert into too much estradiol. If this happens, the use of very low-dose aromatase-inhibiting drugs (0.5 mg of Arimidex® twice a week) may be all that is needed to protect against estrogen overload. Some men don’t need these drugs and can use nutrient formulas that have aromatase-inhibiting properties.
There is no need to guess what you need, as a blood test taken 30-45 days after initiating testosterone-replacement not only reveals a man’s estradiol level, but also ensures that the PSA has not spiked (indicating possible pre-existing prostate cancer), that the dose of testosterone cream is appropriate, and that there are no other side effects occurring.
To view a wide range of estrogen-lowering strategies, one can view Life Extension’s Male Hormone Restoration Protocol.
What if Your Estrogen Level is Too Low?
Some men are so deficient in aromatase that they do not make enough estrogen.
If a blood test reveals estradiol below 20 pg/mL, which may occur if Arimidex®, for example, is being taken at too high a dose, one should consider reducing the dose. Alternatively, applying a tiny dose of a compounded topical estradiol cream to the skin several times a week may also help increase estradiol levels. Follow-up blood tests 30-45 days later can assess if too much or too little topical estradiol cream is being used.
There is also evidence that consuming phytoestrogens from soy might provide similar benefits for the bone75-79 and vascular system.80-88
It is hard to imagine that before 1906, doctors did not even know that a hormone (estrogen) was secreted by the ovaries in women. It was not until 1930 that the isolation of the estrogen complex in pure form was published.
Less than 80 years later, scientists are debating what the optimal levels of estrogen should be in men. This exponential leap in scientific knowledge is a marvel in itself!
The role that estrogen plays in men’s health is an important topic discussed at medical conferences today. As outlined in this article, testing one’s estradiol level is critical because it can be a serious problem if it is too high or if it is too low.
I am pleased to announce that the everyday low price for the Male or Female Blood Test Panels has been reduced from $299 to $269. This price reduction is made possible by the large volume of blood testing Life Extension members have been ordering.
In addition to estradiol, the Male Panel measures PSA, free testosterone, DHEA, C-reactive protein, homocysteine, along with cholesterol lipids, glucose, and blood cell counts and chemistries.
I encourage any member who has not had this comprehensive blood test conducted over the past 12 months to take advantage of this new lower price. To order the Male or Female Panel by phone, call 1-800-208-3444.
If the results reveal estradiol levels are too high or too low, corrective measures can easily be taken to protect your precious health.
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