Testosterone 101: Everything You Need to Know About the Male Sexual Hormone

Testosterone is essential for both men and women, although its role is much more dominant in men. Testosterone is the primary male sex hormone, and it influences muscle growth, sexual health, and several other vital factors.

This article will explore testosterone and its functions.

What is testosterone?

Testosterone is a human sex hormone. It is produced by men in the testicles and by women in the ovaries. Men have much more testosterone than women. Testosterone is typically associated with masculine traits such as muscle definition, body hair, deep voice, etc

How is testosterone made?

Testosterone is produced in several different areas. In men, it is produced primarily in the testicles. In women, it is made in the ovaries as well as the adrenal gland. 

Testosterone is synthesized in the body from cholesterol. Therefore, the body needs a healthy level of cholesterol to produce testosterone, although high cholesterol levels do not necessarily equate to elevated testosterone. 

Testosterone production is maintained and regulated by the brain and the pituitary gland, located at the base of the brain. This gland creates a feedback loop by sending signals to and from the organs responsible for producing testosterone.

When too much testosterone is detected in the blood, the brain signals to the pituitary gland to slow down production. When the opposite is true, the brain tells the pituitary gland to ramp up production. 

Why is testosterone important?

Testosterone is one of the most essential hormones in the human body. It is important for regulating many different biological functions, ranging from our sexual health to the development of bones and muscles.

Testosterone begins to exert its effects more obviously during adolescence. Testosterone levels tend to decrease around age 40.

Benefits and functions of testosterone

Testosterone has a number of important functions in both men and women. Here are a few of the most critical roles that testosterone plays in the human body.

Sexual Development

Testosterone is essential for sexual development in both men and women, but especially in men. For men, testosterone helps to develop the penis and testicles.

Testosterone is also a key hormone for developing and maintaining sex drive in both men and women. High, consistent testosterone levels lead to a steady libido.

In men, testosterone levels also help with sperm production and quality.


Testosterone begins to exert its effects during puberty. Many boys first start to experience the effects of testosterone during adolescence as their voice begins to deepen and they begin to develop body hair.

Boys who do not have a healthy level of testosterone may experience stunted growth during puberty. As a result, they may not experience fully-developed sexual organs, and they may not produce facial hair or body hair.

Muscle quality

Testosterone is vital for both the growth and maintenance of healthy muscle tissue. Bodybuilders and athletes often work with supplements that aim to increase testosterone production because of this. Higher testosterone levels are often associated with increased strength, muscle tone, and more significant muscle development.

Managing mood

Testosterone is also crucial for helping to balance mood. People with testosterone imbalances or deficiencies may be more prone to mood instability, depression, or low self-esteem.

Bone quality

Testosterone is also vital for helping the body regulate and manage bone growth. Healthy testosterone levels are associated with healthy, thick bones. On the other hand, low testosterone levels can cause frail bones.

Testosterone deficiency

Testosterone deficiency and low testosterone can be a problem for both men and women. Men, however, may find the symptoms of testosterone deficiency to be much more apparent and difficult to cope with.

Some different things, including hypogonadism, can cause testosterone deficiency. Hypogonadism is a condition in which the testes are prevented from producing the proper amount of testosterone.

Low testosterone levels can cause several symptoms including:
  • Decreased sex drive
  • Decreased energy levels
  • Increased weight
  • Depression and mood instability
  • Problems with self-esteem
  • Decrease in body hair
  • Thin bones

If you think you’re struggling with testosterone deficiency, then you should discuss the issue with a professional. There are many options to consider that may help restore your testosterone to a healthy level.


Testosterone is an essential hormone in both men and women. Its role is more evident in men, although people of both genders rely on this hormone to help regulate their sex drive, muscle growth, and mood.

The deficiency of testosterone can cause several symptoms that can interfere with life quality. Therefore, understanding the role of testosterone is important for anyone hoping to have a healthy balance of hormones.


  1. . Physiology, Testosterone. NCBI. [Online] [Cited: January 9, 2021.] https://www.ncbi.nlm.nih.gov/books/NBK526128/
  2. Harvard Health Publishing. Testosterone, aging, and the mind. [Online] [Cited: January 1, 2008.] https://www.health.harvard.edu/newsletter_article/testosterone_aging_and_the_mind
  3. David J Handelsman, Angelica L Hirschberg, and Stephane Bermon. Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance. NCBI. [Online] [Cited: July 13, 2018.] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6391653/
  4. JCEM. The Journal of Clinical Endocrinology & Metabolism, Volume 95. [Online] [Cited: February 1, 2010.] https://academic.oup.com/jcem/article/95/2/639/2596855
Back to Blog

Related Articles

Exploring Hypogonadism (Low Testosterone in Men)

Hypogonadism is a condition that can affect men of all ages. The condition involves an individual...