Testosterone is produced by the testicles and ovaries. Too little or too much testosterone production can affect your physical and mental health.
Testosterone is a hormone found in both humans and other animals. In men, the testicles primarily produce testosterone. Women's ovaries also produce testosterone, although in much smaller amounts.
Testosterone production begins to increase significantly during puberty and begins to decline after age 30 or older.
Testosterone is often associated with sexual desire and plays a major role in sperm production. It also affects bone and muscle mass, how men store body fat and even red blood cell production.
A man's testosterone levels can also affect his mood.
Low testosterone levels
- less energy
- weight gain
- feelings of depression
- decreased sex drive
- moodiness
- low self-esteem
- less body hair
- thinner bones
Although testosterone production naturally declines as a man ages, other factors can lower hormone levels.
Testicular injuries and cancer treatments, such as chemotherapy or radiation, can negatively affect testosterone production.
Chronic health conditions and stress can also reduce testosterone production. Some of these include:
- AIDS
- kidney disease
- alcoholism
- cirrhosis of the liver
- low libido
- reduced bone strength
- poor concentration
- depression
Low T levels in women may be due to removal of the ovaries, as well as diseases of the pituitary, hypothalamus, or adrenal glands.
Testosterone therapy may be prescribed for women with low testosterone levels; however, the effectiveness of the treatment in improving sexual or cognitive function in postmenopausal women is unclear.
Testing testosterone
A simple blood test can determine testosterone levels. There is a wide range of normal or healthy levels of testosterone in the bloodstream.
According to the University of Rochester Medical Center, normal male testosterone levels range from 280 to 1,100 nanograms per deciliter (ng/dL) for adult men and 15 to 70 ng/dL for adult women.
Ranges can vary between different labs, so it's important to talk to your doctor about your results.
According to the American Urological Association, if an adult man's testosterone level is less than 300 ng/dL, a doctor can perform a study to determine the cause of the low testosterone level.
Low testosterone levels can be a sign of problems with the pituitary gland. The pituitary gland sends a hormonal signal to the testicles to make more testosterone.
A low T test result in an adult may mean that the pituitary gland is not working properly. But a teenager with low testosterone levels may have delayed puberty.
Moderately high levels of testosterone in men can cause some noticeable symptoms. Boys with high testosterone levels may start puberty earlier. Women with high testosterone may develop masculine characteristics.
Abnormally high levels of testosterone may be due to adrenal gland disorders or testicular cancer.
High levels of testosterone can also occur in less severe conditions. For example, congenital adrenal hyperplasia, which can affect both men and women, is a rare but natural cause of elevated testosterone production.
If your testosterone levels are too high, your doctor may order other tests to find the cause.
Testosterone replacement therapy
Decreased testosterone production, a condition known as hypogonadism, does not always require treatment.
If low T is interfering with your health and quality of life, you may be a candidate for testosterone replacement therapy. Synthetic testosterone can be administered orally, by injection, or with a gel or skin patch.
Replacement therapy can produce desired results, such as increased muscle mass and a stronger sex drive. But treatment does come with some side effects. These include:
- oily skin
- fluid retention
- testicles shrinking
- decrease in sperm production
Some studies have not found an increased risk of prostate cancer with testosterone replacement therapy, but this remains the subject of ongoing research.
One study suggests that testosterone replacement therapy reduces the risk of aggressive prostate cancer, but more research is needed.
The takeaway
Testosterone is commonly associated with male sexual desire. It also affects mental health, bone and muscle mass, fat storage, and red blood cell production.
Abnormally low or high levels can affect a person's physical and mental health.
Your doctor can monitor your testosterone levels with a simple blood test. Testosterone therapy is available to treat men with low testosterone levels.
If you have low testosterone levels, ask your doctor if this type of therapy might benefit you.