Low testosterone: Everything you need to know

Testosterone is a hormone made by the bodies of both people assigned male at birth, and people assigned female at birth. Testosterone plays a role in puberty and fertility, as well as libido — or sexual desire. In people assigned male at birth, most testosterone is made in the testes. In people assigned female at birth, most testosterone is made in the ovaries.

People assigned male at birth have higher levels of testosterone than people assigned female at birth. Testosterone influences the development of many physical characteristics. It helps increase muscle bulk, bone mass, physical strength, and body hair.

The levels of testosterone in your body are constantly changing in response to your body’s needs. However, the overall level of testosterone in your body changes throughout your lifetime as well.

Typically, testosterone decreases as you age — particularly in people assigned male at birth. For some people, these levels can become too low and cause unwanted effects that have them looking for ways to increase their testosterone levels.

There may be certain lifestyle changes to help increase testosterone levels, like adding resistance exercise and losing weight.

Research indicates that resistance exercise, such as lifting weights, is related to temporary increases in testosterone levels.

An older 1999 study suggests that testosterone increases after heavy resistance training are typically much higher in younger men than older men — and overall don’t appear to greatly increase your overall testosterone levels.

Exercise, especially cardiovascular exercise, can contribute to weight loss, which can help to increase levels of testosterone.

Some types of herbal supplements claim to be “testosterone boosters.” The makers of these products claim that the ingredients help to increase levels of testosterone.

However, there isn’t enough research to support their effectiveness, and these products may not actually have ingredients that support their claims.

In fact, a 2020 study evaluated 50 supplements advertised as “testosterone boosting” and “libido improving” and found that less than 25 percent of them had data to support their claims, based on their ingredients. Moreover, 10 percent of the supplements tested contained ingredients that have a negative effect on testosterone, according to the study.

Additionally, these products are not closely regulated by the U.S. Food and Drug Administration. You may find there are more natural steps that may help to boost your testosterone level.

Some foods may play a role in helping your body moderate your testosterone levels.

Making sure you get enough foods that are rich in zinc and vitamin D may help to keep your testosterone at a normal level.

Here are eight testosterone-boosting foods that could help you get the vitamins and minerals you need to keep your testosterone levels healthy.

A 2018 animal study, as well as an older 1996 study on healthy adult men, suggests that zinc supplementation increases testosterone and fertility in those with marginal zinc deficiency.

Testosterone replacement therapy is used to help treat people with abnormally low levels of testosterone.

Abnormally low levels of testosterone can affect normal body functions and may contribute to decreased muscle mass, a reduced sex drive, erectile dysfunction, and mood changes like irritability and depression.

Testosterone replacement therapy involves taking prescribed testosterone medication in the form of pills, patches, and gel that you apply to your skin. Testosterone therapy can also come in the form of injections.

Testosterone injections are one of the more common forms of testosterone replacement therapy. They are typically given by a doctor. You need them less frequently than other forms.

Testosterone replacement therapy has many risks. If you have testosterone replacement therapy, you will need frequent blood tests to check your testosterone levels and to monitor potential side effects, including:

  • fluid retainment
  • acne
  • prostate enlargement
  • reduced fertility
  • sleep apnea
  • blood clots
  • increased red blood cells

Side effects may vary based on the type of testosterone therapy you use.

In order to know whether testosterone levels are too low, a normal level has to be established. This has been a challenge for clinicians. However, according to a press release from the Endocrine Society in January 2017, results from a recent study have helped to define the normal ranges for testosterone levels in men: 264–916 nanograms per deciliter (ng/dL). This range is for men between the ages of 19 years and 39 years who don’t have obesity.

Testosterone levels in people assigned male at birth remain fairly constant from the start of puberty — when levels spike — until a person’s 30s when they slowly begin to decline.

For some people, testosterone levels may become abnormally low.

Symptoms of abnormally low testosterone can be bothersome and may impact your quality of life. These symptoms can include:

If you’re experiencing one or more of these symptoms and don’t believe they’re caused by something else, talk to your doctor. If your doctor thinks your symptoms are related to abnormally low testosterone levels, they can test your levels.

A testosterone test measures the amount of testosterone in your blood. If your doctor wants to test the hormone levels in your blood, they will most likely specify a time of day for your test. Hormone levels are highest in the morning, so this test is often performed in the morning between 7:00 a.m. and 10:00 a.m. Your doctor may have your levels tested more than once.

Your doctor may ask you to stop taking certain drugs before your test, as they could affect your testosterone levels. It’s important to tell your doctor about all medications you’re taking, include both over-the-counter and prescription drugs.

Testosterone home-testing kits are also available from companies such as LetsGetChecked. They use your saliva to test your hormone levels. After taking the test, you’ll send your sample to a lab for testing.

Causes of low testosterone levels include:

  • aging
  • delayed puberty
  • testicular damage (caused by trauma, alcoholism, or mumps)
  • hypothalamic disease
  • pituitary disease
  • noncancerous pituitary tumor
  • chemotherapy

A number of genetic diseases can also affect testosterone levels, including:

Testosterone plays an important role in people assigned female at birth. However, testosterone levels are naturally lower in these individuals than in people assigned male at birth.

Usually, low levels of testosterone in people assigned female at birth aren’t problematic. However, levels that are too high may cause unwanted symptoms. These include:

  • irregular or absent menstrual periods
  • infertility
  • development of facial and body hair
  • deepened voice

High testosterone levels in people assigned female at birth may be caused by:

According to the American Urological Association, you should see a healthcare professional if you have any of the following symptoms of low testosterone, including:

  • reduced sex drive
  • reduced erectile function
  • fatigue
  • reduced lean muscle mass
  • irritability
  • symptoms of depression

Here are answers to the most common questions about low testosterone.

What are the potential benefits of testosterone replacement therapy for people with low testosterone?

Potential benefits of testosterone therapy for people with low testosterone include:

  • increased libido
  • improved sexual function
  • improved mood and wellbeing
  • increased muscle mass
  • increased bone density

Does testosterone replacement therapy work?

There is conflicting evidence regarding the benefits of male testosterone therapy for age-related declines in testosterone, according to a 2017 clinical review.

Some studies show improvement in erectile dysfunction in older men, while others do not. There is no evidence that testosterone therapy improves erectile dysfunction in men with normal testosterone levels.

Testosterone therapy does appear to increase bone density in the lumbar spine in middle-aged men with testosterone deficiency.

It also consistently increases lean mass while decreasing fat mass, but the effect sizes are small.

Are there different adverse effects of testosterone replacement therapy for people assigned male at birth versus people assigned female at birth?

Side effects of testosterone therapy can vary for people based on their sex assigned at birth. Adverse effects of testosterone replacement therapy in people assigned male at birth may include:

  • acne
  • erythrocytosis (when you have more red blood cells than normal)
  • growth of metastatic prostate cancer
  • reduced sperm production
  • increased risk of detecting subclinical prostate cancer

Adverse effects of testosterone therapy in people assigned female at birth may include:

  • acne
  • extra hair growth
  • weight gain
  • fluid retention
  • mood swings
  • anger or hostility

In rare circumstances, adverse effects may include:

  • voice deepening
  • baldness
  • clitoral enlargement

Are there cardiovascular risks to testosterone therapy?

In a 2015 advisory, the Food and Drug Administration (FDA) warned that testosterone use is possibly associated with increased cardiovascular risk. However, other meta-analyses did not find an increased risk. For now, the effects of testosterone therapy on cardiovascular health remain unclear, but studies are ongoing.

Testosterone levels in people assigned male at birth decrease a little naturally with age. However, in some people, these levels can be too low and cause unwanted symptoms. Treatment is available, but it’s important for your doctor to confirm your low testosterone levels with one or more blood tests. Your doctor may also do other tests to help determine what’s causing your low testosterone.

For people assigned female at birth, levels of testosterone that are too high, rather than too low, are more concerning. Symptoms of high testosterone may be an indication of an underlying condition that needs to be treated.