At Men’s Vitality Center in Tucson, we offer testosterone replacement therapy to men who have low testosterone levels. Testosterone replacement therapy can have a transformative effect for men with low T, improving their mood, increasing their muscle mass and bone density, and increasing their energy levels. You may wonder what exactly testosterone does that makes it so important for men. In this blog, we will go over the role testosterone plays in various systems in the body.

Endocrine System

The endocrine system is made up of glands that make hormones. The hypothalamus, a part of the brain, is responsible for telling the pituitary gland how much testosterone is needed, which then sends this message to the testicles. The testicles produce most of the testosterone in the body, though a small amount is produced in the adrenal glands. Testosterone is used to form the testicles before a boy is even born. Later in life, testosterone also helps develop male features such as body hair, facial hair, and a deeper voice.

Reproductive System

Testosterone is responsible for forming the male genitals in utero. In puberty, testosterone levels skyrocket, promoting further growth of the male reproductive system. After that, testosterone helps the testicles produce sperm on a daily basis.


With the growth of the testicles and penis, and the development of sex characteristics such as facial hair and a deeper voice, comes the development of sexual desire. Low levels of testosterone are associated with decreased desire for sex, and may even result in erectile dysfunction.

Central Nervous System

The body controls testosterone by sending messages through the bloodstream using chemicals and hormones. As stated above, the hypothalamus in the brain communicates with the pituitary gland to control the release of testosterone in the testicles. Testosterone plays a part in behaviors, such as dominance, aggression, and competitiveness. Taking part in competitions can actually increase a man’s testosterone levels. When a man has low T, he may experience several cognitive and mental health issues. Some examples include a loss in motivation and confidence, an inability to concentrate, low mood, sleep problems, and fatigue. Keep in mind that testosterone isn’t the sole factor that contributes to these issues, but it does play a role.

Skin and Hair

As a man goes through puberty, testosterone promotes hair growth on the face, armpits, and genitals, and sometimes on the arms, legs, and chest. Men with low T often lose some of their body hair.

Muscle, Fat, and Bone

Testosterone contributes to muscle growth, mass, and strength. It increases the neurotransmitters responsible for tissue growth, and increases the level of growth hormone in the body, making it easier to bulk up during exercise. Additionally, testosterone helps your metabolism, making your body burn fat more efficiently. Men with low testosterone often see an increase in body fat as their testosterone levels lower. Finally, testosterone improves bone density and aids in the manufacturing of red blood cells in bone marrow.

Circulatory System

Testosterone uses the bloodstream to move throughout the body. To discover your testosterone levels, you must take a blood test. As stated above, testosterone helps bone marrow make red blood cells. Some studies also indicate that testosterone is good for your heart. However, there are mixed results on how testosterone affects blood pressure and cholesterol, so it is important to consult with your doctor about testosterone replacement therapy if you are concerned.

As you can see, testosterone is an essential hormone for males. If you are experiencing low testosterone levels, it has an impact on your body as a whole. Fortunately, you don’t have to live with low testosterone. At Men’s Vitality Center in Tucson, we offer testosterone replacement therapy for men with low testosterone. Contact us today to learn more.