In the past, certain complaints and symptoms were attributed to medical conditions such as diabetes, depression, high blood pressure, and coronary artery disease, while the loss of sex drive was typically related to aging. Today, however, there is a growing recognition that testosterone can and does account for many symptoms, and that events such as sudden loss of sex drive are not adequately explained by lower of testosterone as we age.
Testosterone Total and Free, describes a particular hormone found in the blood stream. Produced by the adrenal glands, it affects the body by stimulating various organs -- ovaries in women and testicles in men. It also interacts with other parts of blood serum and combines with certain molecules. The levels of testosterone are compared to normal ranges and also by the patient's sex and age. Low testosterone creates an absence of stimulation, such as a lack of calcium for bone density which can cause brittle bones in older individuals.
Testosterone tests can measure the Total Testosterone
, the overall amount in the blood stream. This type of test indicates how much of the hormone is in the blood and compares it to a range considered to be within normal limits. The reviewer must factor in related items such as sex, age, medical conditions and or medications. The difficulty in relating this number to symptoms is that some of total testosterone binds to certain molecules in the blood. This bound portion of total testosterone is therefore not available to do the work of the hormone- such as stimulation of bone density.
It is important to know testosterone total and free amounts, meaning how much of the total testosterone is not bound to molecules and can therefore stimulate various body functions including sex drive. To assess the possibility of low testosterone, one must measure the amount of free testosterone that affects the body in certain ways, such as the hormonal contribution to the sex drive.
Most total testosterone is not free. Free means simply that it is not bound to something else. Most of the total testosterone is bound to a specific type of cell called the SHBG (sex hormone binding globulin). A smaller portion is connected to a blood protein (albumin). What remains unbound in the blood stream is called free testosterone. This is the part of total and free testosterone that can easily enter cells and affect cell activity. It is also true that anything that lowers the amount of binding will leave more testosterone free to work in stimulating cell activity, which in effect raises the level of free testosterone. The benefits of testosterone supplements depend upon the determination of free testosterone. Merely giving increased levels of testosterone has no predictable benefit without testing for total and free testosterone.
Testosterone Levels What is Normal?
Normal levels are not optimum levels and vary based on your age and gender. Test results will show the normal levels for your exact age. However, for illustrative purposes the following are generally considered normal limits:
Men 270-1070 ng/dL (9-38 nmol/L)
Women 15-70 ng/dL (0.52-2.4 nmol/L)
Free testosterone levels considered within normal limits:
Men 50-210 pg/mL (174-729 pmol/L)
Women 1.0-8.5 pg/mL (3.5-29.5 pmol/L)
Symptoms, Treatment and Monitoring of Low Testosterone (Low T)
Effective treatment of low testosterone can bring immediate and clear results. Sex drive increases and the person generally has more energy. All treatments carry risks for regular testing and monitoring are important. For example, an increase in testosterone in men may also increase the risk of prostate disease.
Related Laboratory Testing
If there is a treatable low testosterone condition, or if the care provider decides only to monitor, a Basic Health Screening can be helpful in establishing baseline and history. This screening can help determine overall health and track changes that affect thyroid, cholesterol, diabetes, and prostate changes in men. Any form of testosterone treatment is made safer by use of testing and monitoring.
Testosterone monitoring and therapy also involve changes to other parts of the body including thyroid function, red and white blood cells, cholesterol, and electrolytes. The initiation of hormone treatment if needed or monitoring would be more useful if baseline information and trends or changes in related systems are also available.