I am currently teaching two sections of Developmental Psychology at a local community college. Recently I posed an extra credit question to my students: “We know that women have low levels of testosterone and that men have low levels of estrogen. Since women don’t have testes and men don’t have ovaries, where do these opposite-sex hormones come from?”
As it turns out, I myself had only half the answer to that question. Sources I have clearly state that testosterone is manufactured in low levels by the adrenal glands in both men and women. However, nowhere have I been able to locate clear information about the locus of estrogen manufacture other than ovaries. I located one source which stated that high levels of estrogen are present in a part of the male reproductive system called the “efferent ducts.” However, this source did not say that the efferent ducts produced the estrogen, only that it was present there. Hell, the article, didn’t even say exactly where the efferent ducts are located!
OK, Straight Dopers, that is my dilemma and my question: what part of the male anatomy produces estrogen? It’s worth extra credit if you know!
Virtually all estrogen production in men comes from conversion of testosterone in the “peripheral tissues”. By and large, “peripheral tissues” means fat tissue.
So, obese men have more estrogen than lean men. Sometimes this contributes to breast enlargement.
In rare states, estrogen can be produced by the testes but this is not at all significant in normal men.
And just in case you’re wondering, the little bit of estrogen that men do have (from conversion of testosterone to estrogen in fat tissue) seems critical for normal health, especially for the bones. Look here for a unique and informative report.
In this case, the human brain can be thought of as “fat tissue” (see Singing Fish). Aromatase is present in brain tissue, and there are several reports that suggest estrogen may act as a minor neurotransmitter.
