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The Most Surprising Facts About Testosterone

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  • Testosterone 101

    Testosterone 101

    When you hear the word “testosterone,” what image comes to mind? Do you picture muscle-bound Mr. Universe contestants, showing off their unbelievably enormous biceps? How about rowdy football fans, rioting in the streets after their team wins a championship?

    While testosterone does work to build muscle mass—and, rather notoriously, contribute to aggressive behavior—there’s much more to this famed hormone.

    Click through the slideshow to learn some surprising new facts about testosterone.

  • Not Just for Men

    Not Just for Men

    While we often associate testosterone with men, women have testosterone, too. In fact, a healthy young woman produces 300 micrograms of testosterone per day.

    Testosterone plays an important role in sexual health. It stimulates desire, increases libido, heightens arousal, and increases sexual satisfaction. Testosterone also helps women maintain bone density, muscle mass, and a healthy energy level.

    Women with low testosterone (low T) may experience decreased libido, persistent fatigue, and a decreased sense of well-being.

  • The Lowdown on Low T

    The Lowdown on Low T

    Low testosterone can also pose problems for men. According to the National Institutes of Health (NIH) 5 million men have low testosterone (NIH, 2009). Low testosterone is defined as less than 300 nanograms/decileter (ng/dL).

    What causes “low T”? As men age, their bodies naturally begin making less testosterone. However, certain diseases, medical treatments, genetic conditions, and lifestyle choices can also incite the decline.

    Men with low T may experience decreased sex drive, erectile dysfunction, fragile bones, and other health issues. 

  • Got Diabetes? Get a Testosterone Test

    Got Diabetes? Get a Testosterone Test

    Men with diabetes are particularly prone to low T. According to the American Diabetes Association, a man with type 2 diabetes is twice as likely to suffer from low T as a man without diabetes (ADA, 2013).

    Why? Low testosterone is often associated with insulin resistance. Insulin resistance means that your body uses insulin less effectively. This causes blood sugar and fat levels to rise, which causes diabetes. If you have diabetes, it’s vital to monitor your testosterone levels.

  • What Testosterone Actually Does

    What Testosterone Actually Does

    But just what does testosterone do, anyway?

    We all know that testosterone helps build muscle and boost sex drive. However, did you know that testosterone is also good for your blood?

    That’s right: the hormone plays a key role in erythropoiesis, which is the production of red blood cells. If you have low testosterone, your body won’t produce as many red blood cells. This decreased cell production may cause a significant drop in energy.

  • Testosterone and Bone Density

    Testosterone and Bone Density

    In addition to building muscle and making red blood cells, testosterone also helps to maintain bone density. If your testosterone level decreases, your bones may become more fragile. Your doctor may order a bone density test to find out whether you have low testosterone.

    Because testosterone works to maintain bone density, low T can cause osteoporosis in men. Doctors often treat this problem with hormone replacement therapy, which can help prevent or slow bone loss.

  • Mental Health and Testosterone

    Mental Health and Testosterone

    As if all of that wasn’t enough, testosterone also plays a vital role in mental health. Testosterone helps maintain energy and a sense of well-being.

    Those with low testosterone often experience a decreased sense of well-being, a depressed mood, and low energy.

    In fact, UCLA researchers found that testosterone replacement therapy improved mood in men with low testosterone (JCEM, 1996). The men treated with supplemental testosterone experienced a decrease in anger, sadness, fatigue, nervousness, as well as increased energy and friendliness.

  • Medical Uses of Testosterone

    Medical Uses of Testosterone

    Given all of the amazing things that testosterone can do, it’s not surprising that it’s used to treat other medical conditions. For example, synthetic testosterone is used to:

    • treat testicular failure
    • suppress lactation
    • treat certain types of breast cancer

    Doctors use hormone replacement therapy to treat men with low T. The patients can take the hormone in the form of an intramuscular injection, a testosterone patch, testosterone gel, or as a gum tablet.

  • Too Much Testosterone?

    Too Much Testosterone?

    Unfortunately, where testosterone is concerned, you can have too much of a good thing.

    High testosterone levels (above 1,200 ng/dL) can indicate:

    • androgen resistance: a condition in which a genetically male person develops female sex characteristics
    • congenital adrenal hyperplasia: a condition in which male characteristics appear early or inappropriately
    • cancer of the ovaries
    • cancer of the testes

    High testosterone also has been linked to increased aggression, and may increase the risk of heart disease.