Testosterone, Free (Direct)

What is testosterone?

Testosterone is a hormone with a potent role in men. While present in women too, it is the protein responsible for male feature development. Testosterone is produced by the testes and the adrenal glands. It is responsible for the changes that happen to boys during puberty. It helps men grow hair, have a deepen voice, grow muscles, well as helps grow his testes and penis. At a later age, testosterone help men’s sex drive and in the production of sperm.

The body’s testosterone levels are dominated by the pituitary gland in the brain. Our body has many glands that play numerous roles. Glands manufacture our hormones. The hypothalamus is a gland located in the brain; it is responsible for telling the pituitary gland (another gland) how much testosterone is needed. As a result, the pituitary gland sends messages to the testicles that begin their hormone production. While the testicles are in charge of making testosterone, a small amount is formed by the adrenal glands (glands located above the kidneys). In women, both ovaries and adrenal glands form testosterone. When a boy is conceived, his testosterone hormones start working on forming the male genitals. When the boy reaches puberty, the work becomes accentuates and male attributes start becoming more pronounced.

While most of this hormone is attached to binders like albumin and SHBG, some remain unbound and roaming freely in the body. This is called FT or free testosterone. Both free testosterone and testosterone that is bound to albumin are considered to be bioavailable are ready to be used directly by our body for its functions.

Testosterone is a very important hormone that has a major effect on our body and development. Men start producing testosterone seven weeks post-delivery. These levels start rising to peak during the late teens, after which they level off. When the man turns 30, levels may start decreasing. It is normal for testosterone levels to drop by 1% every year after this age. A healthy man produces enough testosterone, despite the age-related declines. When low levels are produced, it is refereed to as hypogonadism that would require a hormonal therapy treatment to balance the hormone’s levels. This HT should not be an option for men with normal levels of Testosterone.

The Free testosterone test measures the amount of free unbound testosterone in the blood. This circulating hormone spurs the bone marrow to make more red blood cells. It also has a protective effect on the heart.

Why take the free testosterone test?

This test can help detect if you have abnormal levels of testosterone, whether you are a man or a woman. If you are a man, it can help explain the cause of your erectile dysfunction or why your partner is not being able to get pregnant. If you are a woman, it can help explain why you have been developing some virile features, why you are infertile and whether you have PCOS (polycystic ovary syndrome). This condition is accompanied by insulin resistance, carbohydrate resistance, low levels of HDL (The good cholesterol), high levels of triglycerides, high levels of LDL (the bad cholesterol), obesity and elevated blood pressure. These side effects of PCOS do increase the risks of heart disease in women. Children, who get tested for testosterone, are those who may have unclear genitalia or have delayed or a very early puberty. High testosterone levels in young boys can lead to precocious puberty. A condition that could be the result of tumors and congenital adrenal hyperplasia.

A woman needs to get tested if she has signs of high testosterone levels as they may lead to numerous conditions like infertility, lack of menstruation, acne, obesity, high blood sugar levels, hair thinning on the scalp, and the growth of extra hair on the face.

Men, who are showing signs of low testosterone levels, need to get tested too to avoid other side effects, such as a low sex drive, low energy, bone loss and infertility. Men who have been showing signs of andropause need to test their levels of testosterone. This late-onset hypogonadism may cause anemia, depression, low bone density, lack of energy and fatigue, poor concentration, ED and infertility. Studies have linked low testosterone levels to diabetes in men. Testosterone can help the body take up a higher level of glucose when insulin is released. When a man has low levels of testosterone, he develops insulin resistance: a condition where the body needs to make more insulin to balance blood sugar levels. A study published at the Journal of Clinical Endocrinology and Metabolism, explained that 20 studies observing more than 2850 men showed diabetic men to have low testosterone levels.

Men and women who have been trying to conceive but are not succeeding need to get their testosterone levels tested. also, Men who have been having problems getting and maintaining an erection should check their free testosterone levels to rule our ED.

What causes the levels of Free Testosterone levels to rise?

You need to pay attention, when taking this test, that some medications, herbs and vitamins can alter your normal levels. This could lead to misdiagnosis, as well as unnecessary tests and treatments.

What your Free Testosterone test results mean

The normal ranges of Free Testosterone differ with age and gender. These are the normal values:

• Between the ages of 0 and 19: Free testosterone levels are not established for both boys and girls.
• For women who are above the age of 19 years, Free testosterone levels need to be between 0 and 4.2 pg/mL.
• For men who are between the ages of 20 and 29, levels need to be between 9.3 and 26.5 pg/mL.
• For men who are between the ages of 30 and 39, levels need to be between 8.7 and 25.1 pg/mL.
• For men who are between the ages of 40 and 49, levels need to be between 6.8 and 21.5 pg/mL.
• For men who are between the ages of 50 and 59, levels need to be between 7.2 and 24.0 pg/mL.
• For men who are above 59 years, levels need to be between 6.6 and 18.1 pg/mL.

Men who have low free testosterone levels may be prescribed testosterone therapy; however the FDA has not approved this hormone therapy for women. Some natural methods to boost testosterone levels include having a proper diet that is high in proteins and healthy fats, working out, sleeping well, learning techniques to manage stress, and stopping smoking.

High levels of testosterone in men can be caused by tumors in the testicles and adrenal glands, early puberty in boys, and congenital adrenal hyperplasia. High levels of testosterone in women can be caused by PCOS, ovarian tumors, adrenal glands tumors, or congenital hyperplasia.

Low levels of testosterone in men can be caused by hypothalamic or pituitary disease, genetic illnesses that may cause low levels of testosterone, alcoholism, physical injury, or viral diseases like mumps. Some chronic conditions may lead to hypogonadism, including diabetes.

Where can I get a Free Testosterone test near me?

Please use our Lab Locator to find find a convenient testing location.

Reviewed By: Dr. Kurt Kloss, MD
Last Reviewed Date: May 26, 2021