Testosterone is a hormone found in humans, as well as in other animals. In men, the testicles primarily make testosterone. Women’s ovaries also make testosterone, though in much smaller amounts.
The production of testosterone starts to increase significantly during puberty and begins to dip after age 30 or so.
Testosterone is most often associated with sex drive and plays a vital role in sperm production. It also affects bone and muscle mass, the way men store fat in the body, and even red blood cell production.
A man’s testosterone levels can also affect his mood.
Low testosterone levels
Low levels of testosterone, also called low T levels, can produce a variety of symptoms in men, including:
- decreased sex drive
- less energy
- weight gain
- feelings of depression
- moodiness
- low self-esteem
- less body hair
- thinner bones
While testosterone production naturally tapers off as a man ages, other factors can cause hormone levels to drop.
Injury to the testicles 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
Testosterone levels decline steadily in adult women, however, low T levels can also produce a variety of symptoms, including:
- low libido
- reduced bone strength
- poor concentration
- depression
Testing testosterone
A simple blood test can determine testosterone levels. There’s a wide range of normal or healthy levels of testosterone circulating in the bloodstream.
Normal male testosterone levels range between 280 and 1,100 nanograms per deciliter (ng/dL) for adult males, and between 15 and 70 ng/dL for adult females, according to the University of Rochester Medical Center.
Ranges can vary among different labs, so it’s important to speak with your doctor about your results.
If an adult male’s testosterone levels are below 300 ng/dL, a doctor may do a workup to determine the cause of low testosterone, according to the American Urological Association.
Low testosterone levels could be a sign of pituitary gland problems. The pituitary gland sends a signaling hormone to the testicles to produce more testosterone.
Low T-test results in an adult man could mean the pituitary gland isn’t working properly. But a young teen with low testosterone levels might be experiencing delayed puberty.
Moderately elevated testosterone levels in men may produce few noticeable symptoms. Boys with higher levels of testosterone may begin puberty earlier. Women with high testosterone may develop masculine features.
Abnormally high levels of testosterone could be the result of an adrenal gland disorder or even cancer of the testes.
High testosterone levels may also occur in less serious conditions. For example, congenital adrenal hyperplasia, which can affect males and females, is a rare but natural cause for elevated testosterone production.
If your testosterone levels are extremely high, your doctor may order other tests to find out the cause.
Testosterone is the most critical hormone for men. It is the primary “androgen,” or male hormone. Testosterone controls male physical features and most of the attributes of “maleness.”
In men and boys, testosterone plays several important roles, such as:
- The development of the penis and testes
- The deepening of the voice during puberty
- The appearance of facial and pubic hair starts at puberty; later in life, it may play a role in balding
- Muscle size and strength
- Bone growth and strength
- Sex drive (libido)
- Sperm production
At all ages, for these reasons and more, testosterone is critical to a man’s quality of life.
WHERE IS TESTOSTERONE PRODUCED?
Testosterone in men is made by the male sex organs, the testes. The hypothalamus and the pituitary gland are important in controlling the amount of testosterone produced by the testes. In response to the release of other hormones by the hypothalamus, the pituitary gland produces a luteinizing hormone that travels in the bloodstream to the testes, which stimulates the production and release of testosterone.
WHY IS TESTOSTERONE SO IMPORTANT TO MEN?
An adequate supply of testosterone is required for the development and maturity, physically, emotionally, and mentally, of boys to men. However, testosterone’s importance to men goes well beyond sexual maturity. Testosterone also plays a vital role in:
- The building of muscle and bone
- Helping to metabolize fat
- Regulating sleep
- Improving mood
- Improving cognitive abilities
In addition, testosterone is essential to having a happy and healthy sex life. Testosterone has also been linked to maintaining a healthy heart and lowering your risk of developing cardiovascular disease.
Testosterone is the most critical hormone to a man’s health, vitality, and wellness.
HOW DOES TESTOSTERONE IMPACT THE REPRODUCTIVE SYSTEM?
Testosterone impacts a man’s ability to father a child. Testosterone is required for sperm production, but it is other hormones, and not testosterone, that stimulates the production of sperm. Men who may be having fertility issues could be suffering from low testosterone. Male infertility can have many causes, not all of which are related to sperm count. Other issues can also influence a man’s ability to conceive a child, such as:
- Libido or sex drive
- Erectile dysfunction (ED)
- Sperm motility, or their ability to swim
Testosterone levels are related to all the above. Men with low testosterone may have decreased sperm count, weak or less motile sperm, and low libido, as well as ED. Low testosterone may not directly cause infertility. But it can lower sperm count, and negatively impact your ability to father a child in several ways.
HOW DOES TESTOSTERONE IMPACT A MAN’S PSYCHO-EMOTIONAL WELL-BEING?
Testosterone also has a significant influence on a man’s emotional states. Testosterone has been shown to play an important role in supporting cognitive abilities and a man’s ability to focus on organizational tasks. In addition, less than normal testosterone levels can trigger any number of negative emotional states. Low testosterone has been associated with:
- Increased irritability
- Mood swings
- Increased anxiety and depression
- Increased levels of stress
Most of the testosterone’s impact on cognition and emotional states is related to the fact that it is a necessary precursor to critical “brain chemicals,” known as neurotransmitters. Two of the most important of these “feel-good chemicals” are dopamine and serotonin, both of which rely on testosterone for their production.
