What Are Normal Testosterone Readings for Men?

Men who have had a blood test to check their testosterone levels may wonder what a normal range should be for their test results. Testosterone levels either too high or too low can affect health and indicate disease, illness and other health issues.

Definition

• Testosterone is a sex hormone present in larger quantities in men and lesser quantities in women. This hormone produces muscle and bone growth and stimulates male sex characteristics.

Normal Readings in Men

• An average testosterone level falls within a wide range, as levels vary from man to man based on age, genetics, size, illness, time of day tested and other factors. According to Diagnose-Me, normal levels range from 300 to 1,000 ng/dl.

Too High

• Increased testosterone levels in men may indicate testicular tumors, steroid use, early puberty, adrenal tumors, congenital adrenal hyperplasia and hyperthyroidism.

Too Low

• Decreased testosterone levels in men, known as hypogonadism, can signify several things, including genetic diseases such as Kallman's, Prader-Willi and Klinefelter's; damage to the testes from injury, alcoholism or mumps; and pituitary disease.

Age and Testosterone

• Young men ages 14 to 20 experience their highest levels of testosterone during this time. As men age, the levels gradually lessen, potentially causing loss of appetite, depression, inability to grow muscle, fatigue and loss of libido.