By Dr. Mercola
Testosterone, a hormone produced primarily by the testicles, is often associated with the epitome of "manhood" (although women have testosterone, too).
Indeed, it does play a large role in male sexuality and reproduction, impacting such factors as sexual and reproductive function, muscle mass, and hair growth, but also has some less "flashy," albeit equally important, roles like maintaining bone density, levels of red blood cells and a sense of well-being.
Beginning around age 30, a man's testosterone levels begin to decline, and continue to do so as he ages.
A wide range of chemical exposures included prescribed drugs like statins, adversely impact testosterone production in men. At the same time, estrogen levels typically increase due to widespread exposures to estrogen-mimicking compounds in food, water and environmental pollutants.
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