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Low testosterone in males is common as they get older. Symptoms can be subtle, but there is treatment available if the symptoms affect your lifestyle.

Testosterone is a hormone produced by the testicles. Testosterone affects your appearance and sexual development, stimulates sperm production and sex drive, and helps build muscle and bone mass.

Testosterone production typically decreases with age. According to the American Urological Association, about 40 percent of males ages 45 and older have low testosterone.

If your testosterone production drastically drops, you may experience a range of symptoms. Signs of low testosterone are often subtle and can include:

Language matters

Though sex and gender exist on a spectrum, the studies and surveys below used the terms “male” and “men” and did not report data on, or include, participants who were transgender, nonbinary, gender nonconforming, genderqueer, agender, or genderless.

To maintain the specificity and accuracy of the research, this article will use the terms “male” and “men” throughout.

Testosterone plays a key role in sex drive, also known as libido. Some people may experience a decline in sex drive as they get older, but those with low testosterone will likely experience a more drastic drop.

Testosterone aids in achieving and maintaining an erection. It tells brain receptors to produce nitric oxide, which is a molecule that helps trigger a series of chemical reactions necessary for an erection to occur.

When testosterone levels are too low, you may have difficulty achieving an erection before sex or having spontaneous erections, such as during sleep.

However, research is inconclusive on whether testosterone replacement therapy can successfully treat erectile dysfunction. In a 2016 review of studies that looked at the benefit of testosterone in men with erection difficulties, nearly half showed no improvement with testosterone treatment.

Other health conditions can often cause erectile difficulties. These include:

Smoking and alcohol use can also contribute.

Experiencing hot flashes can be a sign of low testosterone. This can feel like a sudden sensation of warmth. You may also experience heavy sweating, reddening of the skin, and night sweats.

Testosterone plays a role in several body functions, including hair production. Balding is a natural part of growing older for many men, and while it can be hereditary, those with low testosterone may lose body and facial hair as well.

Males with low testosterone may report extreme fatigue and decreased energy. You may have low testosterone if you’re consistently tired despite getting plenty of sleep or if you find it harder to get motivated to exercise.

Males with low testosterone may notice a decrease in muscle mass, as testosterone contributes to building muscle. A 2016 review found that testosterone affects muscle mass but not necessarily strength or function.

Males with low testosterone may experience increased body fat or develop gynecomastia, which is enlarged breast tissue. Gynecomastia can occur when there is an imbalance of testosterone and estrogen in the body.

Osteoporosis is a condition many people often associate with females, but males with low testosterone can also experience bone loss. Testosterone helps produce and strengthen bone, so males with low testosterone, especially older men, may have lower bone volume and be more susceptible to bone fractures.

Males with low testosterone can experience mood changes. Since testosterone influences many of the body’s physical processes, it can also influence mood and mental capacity.

Both testosterone levels and cognitive functions, particularly memory, decline with age. As a result, doctors have theorized that lower testosterone levels could contribute to affected memory.

According to a 2019 review of studies, testosterone supplementation is linked with improved memory in older men with low testosterone though the effect may be small.

However, a 2017 study on testosterone supplementation did not find memory improvements in 493 men with low testosterone levels who took testosterone or a placebo.

The body requires testosterone to develop the penis and testicles, so low testosterone levels could contribute to a disproportionately smaller penis or testicles. There are other conditions and circumstances that can cause a smaller penis and testicles, as well.

These include:

Doctors have linked low testosterone with an increased risk for anemia, according to a 2017 study. When the researchers administered testosterone gel to anemic men with low testosterone, they saw improved blood counts compared to men who used a placebo.

Some symptoms of anemia include:

  • difficulty concentrating
  • dizziness
  • leg cramping
  • difficulty sleeping
  • rapid heart rate

Testosterone levels naturally decrease as males get older, but other conditions or circumstances may also cause low testosterone. These may include:

Having low testosterone may increase your risk of developing other health conditions.

These conditions include:

  • osteoporosis
  • diabetes
  • heart disease

Testosterone levels are typically 300 to 1,000 nanograms per deciliter (ng/dL). Low testosterone is when testosterone levels fall below 300 ng/dL. A blood test called a serum testosterone test can determine your testosterone level.

Other tests may be performed to determine the cause of low testosterone.

Tests to diagnose low testosterone and its causes include:

  • serum testosterone
  • luteinizing hormone
  • blood prolactin level

Testosterone replacement therapy is a common treatment for low testosterone.

Testosterone replacement therapy

If you have low testosterone symptoms that are bothering you, you can talk with a doctor to determine if testosterone replacement therapy is right for you. Testosterone replacement therapy comes in a variety of forms, including:

  • oral medications
  • skin gel
  • injections
  • pellets placed under your skin
  • patches

Testosterone replacement therapy is a lifelong treatment. If you stop treatment, your testosterone levels will also drop.

Side effects of testosterone replacement therapy can include:

  • acne
  • enlarged prostate
  • shrinking testicles
  • decreased sperm count
  • high red blood cell count
  • fluid retention
  • swollen feet or ankles

Testosterone replacement therapy may not be right for you if you:

  • have an untreated heart condition
  • have breast or prostate cancer
  • have sleep apnea
  • have elevated red blood cell counts
  • plan to have children

Males experience a gradual decrease in testosterone as they get older. The older you are, the more likely that you’ll have low testosterone.

A variety of factors can cause low testosterone. Males with testosterone levels below 300 ng/dL may experience some symptoms. A doctor can check your testosterone level with a simple blood test.

If you have low testosterone and the symptoms bother you, testosterone replacement therapy is a common treatment.

If you would like to know your testosterone levels, LetsGetChecked offers male hormone tests at home at various price points.

Read this article in Spanish.