Everyone knows that testosterone is the "male" hormone. It plays a role in sex drive, sperm production, fat distribution, red cell production, and maintenance of muscle strength and mass, and it’s associated with overall health and well-being in men. What many people don’t realize is that it’s important for women, too! In fact, men and women are the reverse of each other in terms of their hormone percentages: Men have 10 times as much testosterone as women, and for estrogen, it’s the opposite.
It’s well-known that testosterone helps to build muscle. If two twins—one male and one female—lived in the exact same environment from age 7 to age 20, the male twin will still put on a lot more muscle than his sister, simply by virtue of having much more testosterone. This also means that if a woman has even lower testosterone levels than she normally would, she would struggle even more to build muscle and maintain her existing muscle and would also have a hard time maintaining her bone mass.
This becomes very important for aging women because they have less muscle and bone to begin with. As people grow older, they naturally lose muscle mass, bone mass, flexibility, and mobility—all of which are critical for longevity and a happy life. Retaining what testosterone you have is therefore crucially important to maintaining that muscle and bone mass. Unfortunately, a lot of even young women lower their testosterone by taking endocrine-disrupting pseudo-hormones like birth control pills, which lower their sex hormone binding globulin (SHBG), which carries sex hormones through the blood. Birth control is convenient and has its benefits, but many young women don’t realize they are also lowering their muscle and bone mass by taking it.
Testosterone receptors are all over the body—including the reproductive organs, arteries, and brain—and they have an important role to play in a number of different bodily processes. Testosterone is widely recognized as the hormone responsible for sexual desire and sexual response in both sexes. Libido and orgasmic function are both related to testosterone, too. Since sexual desire and function are closely linked to reproduction and the survival of the species, it’s quite understandable that testosterone is also involved with critical functions such as cognition and cardiovascular health.
In women as well as in men, testosterone helps cognitive function and protects us against depression. It’s a common complaint of women with low testosterone to have "low mood"––not depression, but nonetheless a persistent feeling of anxiety and sadness that can become depression. Fatigue can also be an issue; when a woman has low testosterone, there is often a loss of excitement and zest for life. By the age of 40, the testosterone levels of a woman are typically half of what they were when she was 20, and this is often when these symptoms manifest.
I hope that in time, there is more research conducted on hormone replacement therapy to counteract the negative effects of low testosterone in women—especially as they get older. Testosterone is not a "male hormone" as some people like to think––it’s a hormone for every human, and it’s necessary for every woman to feel whole and happy. All hormones deliver critical messages and "multitask" in different ways. Testosterone is no different!