Testosterone has many functions and is responsible for normal growth, the development of male sex organs, and the maintenance of secondary sexual characteristics.

Testosterone is also important for maintaining

  • Muscle mass.
  • The right levels of red blood cells.
  • Bone growth.
  • Sensation of well-being.
  • Sexual function.

The production and secretion of testosterone is highly controlled by some other glands in the body and their hormones. The main controllers are undoubtedly the hypothalamus and the pituitary gland. The hypothalamus is secreting gonadotropin-releasing hormone (GnRH) which controls the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) produced by the pituitary gland.

Luteinizing hormone regulates the production and secretion of testosterone by the Leydig cells of the testicles.

FSH stimulates spermatogenesis.

Another important fact is that women have a low testosterone level. It is being produced by the teak cells of the ovaries, by the placenta, as well as by the adrenal cortex, in both sexes.

Effects of Testosterone on Human Health

Prenatal effects:

  • Genital Virilization
  • Development of the prostate and seminal vesicles

The first postnatal effects:

  • Adult body odor
  • Increased oiliness of skin and hair, acne.
  • Axillary hair
  • Accelerated bone maturation.

Advanced postnatal effects:

  • Increased libido and erection frequency.
  • Pubic hair extends toward the navel.
  • Facial hair.
  • Hair on the chest.
  • Subcutaneous fat on the face.
  • Increased muscle strength and mass.
  • Deepening of the voice.
  • Growth of Adam’s apple.
  • Growth of spermatogenesis tissue in the testicles, male fertility.
  • The shoulders widen and the rib cage expands.
  • The completion of bone maturation and the completion of growth.

Causes of testosterone deficiency

Testosterone deficiency of the testicles is unable to produce normal levels of testosterone.

This deficiency may be physiological or pathological. Physiological deficiency occurs with age. As a man ages, the amount of testosterone in his body gradually decreases. This natural decline begins after age 30 and continues throughout life.

In healthy men 20 to 40 years of age, the early morning testosterone level should be 21.8 nmol/L (627 ng/dL).

What are the symptoms of testosterone deficiency?

Testosterone deficiency has many effects on the body. The most common effects of testosterone deficiency in men are:

  • Decreased sexual desire
  • Erectile dysfunction
  • Feelings of depression
  • Decreased sense of well-being
  • Difficulty concentrating
  • There are also several other changes that occur in the body, such as:
  • Decreased muscle mass, with an increase in body fat
  • Changes in cholesterol levels
  • Decreased hemoglobin and possibly mild anemia.
  • Fragility in the bones (osteoporosis)
  • Decreased body hair

Primary testicular failure is causing a condition called hypergonadotropic hypogonadism. In this condition, testosterone levels are low and pituitary gonadotropin hormones are high.

In secondary or hypogonadotropic hypogonadism, it causes a decrease in the secretion of gonadotropic pituitary hormones.

Prepubertal hypogonadism is characterized by infantile genitalia and lack of virilization.

Hypogonadism after puberty results in decreased libido, erectile dysfunction, infertility, gynecomastia, deterioration of masculinization, changes in body composition, reduction of facial and body hair, and osteoporosis.

Testosterone deficiency

Symptoms

  • Fatigue
  • Lethargy
  • Depression
  • Impotence
  • Loss of libido
  • Muscle weakness
  • Decreased shaving frequency

Signs

  • Loss of body, facial, and pubic hair
  • Gynecomastia (augmentation of breast tissue)
  • Wrinkled skin, especially the face
  • Reduced testicular volume
  • Long-term risk
  • Osteoporosis can occur in untreated patients, leading to an increased risk of hip and spine fractures.

Testosterone Replacement Therapy

What are the best candidates for testosterone replacement therapy? Men should only be treated if blood tests show a low testosterone level. The average man produces 4-7 mg of testosterone per day in a circadian pattern. Evaluation of possible candidates for testosterone replacement therapy should include a complete medical history and hormonal screening.

When testosterone levels in the blood are normal, it means that treatment will not help in relieving symptoms. Men with primary hypogonadism are the best candidates for testosterone replacement therapy. Men who have prostate cancer or breast cancer should not take testosterone replacement therapy.

Successful management of testosterone replacement therapy requires proper evaluation and an understanding of the benefits and risks of treatment. Legally, the use of testosterone to improve athletic performance or correct undersize is potentially dangerous and inappropriate.

There are many pros and cons to this treatment. It has been shown that several symptoms can significantly benefit from this therapy. Some of them are:

  • Low sexual desire
  • Erection Problems
  • Reduced muscle mass and bone density

Advantages of Testosterone Replacement Therapy

There are a number of benefits of testosterone replacement therapy that have been demonstrated and evaluated. It has many positive effects on mood, energy levels and libido.

Transdermal testosterone replacement therapy, in particular, has been linked to positive effects on fatigue, mood, and sexual function, as well as significant increases in sexual activity.

Positive effects on body composition as well as improvements in bone density are also evident. These effects are usually seen within 3 to 6 weeks.