Many physicians that prescribe testosterone use an “estrogen blocker” (arimidex or chrysin) to reduce the peripheral conversion of testosterone into the hormone estrogen. They do this because they claim high levels of estrogen in men can adversely affect the prostate gland. What they fail to realize is that estrogen in men plays a critical role in preventing bone loss, preventing Alzheimer’s disease and dementia and also reducing the risk of cardiovascular disease. There is not one human study that shows estrogen in men is harmful. To the contrary I can produce 50 studies showing estrogens protective effects on bone, brain and the heart. So the question is why do they use “estrogen blockers”?
A long time ago there was study in rats that showed the following: in rats that had an existing prostate cancer, when they were given both testosterone and estrogen their cancers became worse. From that one study in rats, physicians have been taught to block the peripheral conversion of testosterone into estrogen (more on this below). And because one doctor starting teaching this to physicians it has become common practice. Most doctors learn how to dose hormones after residency because in residency training we learn how to treat disease, not prevent it. As a result, there are thousands of men who are blocking estrogen and losing its protection.
If you ask most doctors who use “estrogen blockers” what the typical estrogen level in a healthy 20 year old male they would not be able to give you the correct answer (which is 75 by the way which is equal to what women have in the first half of their menstrual cycle). Yet when they give men testosterone they are taught to block estrogen if the level gets over 50. If estrogen levels above 50 were detrimental to mens health then why aren’t we blocking it in every healthy 20 year old who comes into the office? They don’t have a good answer to that question.
Isn’t estrogen a female hormone? The answer is it is primarily a female hormone but men have it to (just like women make testosterone yet it is primarily a male hormone). The majority of estrogen in men comes from the conversion of testosterone to estrogen by an enzyme called aromatase and typically happens in fat cells. Levels in men remain relatively high throughout adulthood despite declining testosterone levels because there is an increase in fat the occurs in aging.
Why believe what I am writing? When your doctor recommends any treatment it should be because the medical literature and studies support it. Doctors who block estrogen in men can not produce one human study showing that it is harmful. That is huge! Here are 3 of 50 articles I can produce proving estrogen is beneficial in men and should not be blocked:
“Higher estrogen levels were associates with a lower risk for cardiovascular events in men.” Annals of Internal Medicine 1 August, Vol 145 Issue 3;176-84
“In healthy older men, improvement in verbal memory induced by testosterone administration depends on aromatization of testosterone to estradiol.” Neurology 2005;64:290-296
“We conclude that oral estrogen in men reduces homocysteine, fibrinogen and PAI-1 concentrations and favorably influences VLDL, LDL and HDL subclass levels without increasing markers of thrombotic risk.” Atherosclerosis. 1998 Apr; 137(2):359-66
If you are using an “estrogen blocker” you need to inform your doctor of what the literature says about estrogen protecting you against hip fractures, bone loss, heart disease and dementia.
The reason why I am an expert in hormone replacement is because I have read all the literature that supports why I treat patients the way I do as opposed to attending a weekend lecture where one doctor says to block estrogen and taking that at face value.
If your would like my professional opinion on your hormone regimen feel free to call me directly at 949-529-0493.