Interpretation of Free Testosterone, Estrogen, and Total Testosterone Blood Tests
Found this while researching. Some good info here
One can easily determine if they need testosterone replacement or estrogen suppression by adhering to the following guidelines.
Free Testosterone. Free testosterone blood levels should be at the high-normal of the reference range. We define high-normal range as the upper one third of the reference range. Under no circumstances should free or total testosterone be above the high end of the normal range.
What too often happens is that a standard laboratory "reference range" deceives a man (and his physician) into believing that proper hormone balance exists because the results of a free testosterone test fall within the "normal" range. The following charts show a wide range of so-called "normal" ranges of testosterone for men of various ages. While these normal ranges may reflect population "averages," the objective for most men over age 40 is to be in the upper one-third tes-tosterone range of the 21- to 29-year-old group. Based on the following reference range chart from LabCorp, this means that optimal free testosterone levels should be between 21-26.5 nanogram/dL in aging men.
Reference Intervals for Free Testosterone from LabCorp
* 20-29 years 9.3-26.5 picogram/mL
* 30-39 years 8.7-25.1 picogram/mL
* 40-49 years 6.8-21.5 picogram/mL
* 50-59 years 7.2-24.0 picogram/mL
* 60+ years 6.6-18.1 picogram/mL
An example of how this chart can be deceptive would be if a 50-year-old man presented symptoms of testosterone deficiency (depression, low energy, abdominal obesity, angina, etc.), but his blood test revealed his free testosterone to be 9 picogram/mL. His doctor might tell him he is fine because he falls within the normal "reference range." The reality may be that to achieve optimal benefits, testosterone levels should be between 21-26.5 picogram/mL. That means a man could have less than half the amount of testosterone needed to overcome symptoms of a tes-tosterone deficiency, but his doctor will not prescribe testosterone replacement because the man falls within the "average" parameters. That is why it is so important to differentiate between "average" and "optimal." Average 50-year-old men often have the symptoms of having too little testosterone. Yet since so many 50-year-old men have lower than desired testosterone levels, this is considered to be "normal" when it comes to standard laboratory reference ranges.
The Life Extension Foundation would like to point out that there is disagreement between clinicians and laboratories on the best method for measuring tes-tosterone status. There are different schools of thought as to which form of testosterone should be measured and which analytical procedure provides the most accurate assessment of metabolic activity.
To illistrate this point, the reference values for measuring free testosterone from Quest Diagnostics follow.
Adult Male (20-60+ years): 1.0-2.7% 50-210 pg/mL
Optimal Range: 150-210 pg/mL for aging men without prostate cancer.
We believe that direct testing for free testosterone is the best way to test for testosterone activity, as free testosterone is active testosterone and consists of only 1-2% of total testosterone. Total testosterone can be good for general testing. The four main methods presently used for analyzing free testosterone are:
* Direct, Free Testosterone by Direct Analog/Radioimmunoassay (RIA)
* Testosterone Free by Ultrafiltration (UF)
* Testosterone Free by Equilibrium Tracer Dialysis (ETD)
* Testosterone Free and Weakly Bound by Radioasssay (FWRA)
The latter three test methods are older, more complicated methods that are technically demanding. The direct RIA test has a number of commercial test kits available, and they are better used in today's automated equipment, making this test less tedious and requiring a smaller (less) sample. These advantages have convinced many laboratories and clinics to prefer direct RIA testing for free testosterone. The Life Extension Foundation agrees with this assessment, and therefore uses and recommends the direct free testosterone test with the above-mentioned reference levels.
Consequently, if your doctor tests your free tes-tosterone, be sure you know the analytical method used. If your test results have a reference range as follows, you have probably been tested with one of the other test methods:
Male Reference Range - Test Type
* 66-417 nanogram/dL FWRA
* 12.3-63% %FWRA
* 5-21 nanogram/dL UF or ETD
* 50-210 picogram/mL UF or ETD
* 1.0-2.7% % of free by UF or ETD
No matter what test method is used to determine your free testosterone status, the optimal level (where you want to be) is in the upper one-third of normal for a 20-29 year old male.
Estrogen
Estrogen (measured as estradiol) should be in the mid- to lower-normal range. If estradiol levels are in the upper one-third of the normal reference range, or above the normal reference range, this excessive level of estrogen should be reduced. Labcorp lists a reference range of between 3-70 picogram/mL for estradiol while Quest states a reference range of between 10-50. For optimal health, estradiol should be in the range of 10-30 picogram/mL for a man of any age.
The fact that most aging men have too much estrogen does not mean it is acceptable for a man to have low estrogen. Estrogen is used by men to maintain bone density, and abnormally low estrogen levels may increase the risk for prostate cancer and osteoporosis. The objective is to achieve hormone balance, not to create sky-high testosterone levels without enough estrogen. The problem is that, if we do nothing, most men will have too much estrogen and far too little testosterone.
Total Testosterone
Some men have their total testosterone measured. Standard reference ranges are between 241-827 nanograms/dL for most laboratories. Many older men are below 241. Optimal levels of total testosterone for most men are between 500-827 nanograms/dL. If your levels are lower than 500 nanograms/dL or even a little higher and you still have symptoms, you should check your free testosterone by the Direct (RIA) method.
For other hormone tests, the following are considered to be optimal:
Where You Want to Be - Comment
PSA Under 2.6 ng/mL - (optimal range) Standard reference range is up to 4, but if your level is persistently 2.6 or above, have a blood test to measure the percentage of free vs. bound PSA and a digital rectal exam to help rule out prostate cancer.
DHEA 400-560 mcg/dL - (optimal range) For older men, standard DHEA ranges are very low. It is important for men without prostate cancer to restore them to the youthful range (400-560).
DHT 20-50 nanogram/dL - (optimal range) Reference range is 30-85. DHT is 10 times more androgenic than testosterone and has been implicated in prostate problems and hair loss.
Luteinizing hormone (LH) Age 20-70: 1.5-9.3 mIU/mL 70+: 3.1-34.6 mIU/mL (standard reference ranges) - Under 9.3 mIU/mL - (optimal range) If these levels are high, it is an indication of testicular testosterone production deficiency. LH tells the testes to produce testosterone. If there is too little testosterone present, the pituitary gland secretes more LH in a futile effort to stimulate testicular testosterone production. Testosterone replacement therapy should suppress excess LH levels. Low LH can also be a sign of estrogen overload, since too much estrogen can suppress LH activity. This could mean using an estrogen blocker like Arimidex could solve a testosterone deficiency problem.
Sex Hormone Binding - Under 30 nanomoles/L - (optimal range) Reference range is 13-71 nanomole/L. Excessive binding inactivates testosterone (297).
There are five possible reasons why free testosterone levels may be low-normal (below the upper third of the highest number of the reference range):
* Too much testosterone is being converted to estradiol by excess aromatase enzyme and/or the liver is failing to adequately detoxify surplus estrogen. Excess aromatase enzyme and/or liver dysfunction is likely the cause if estradiol levels are over 30.
* Remember, aromatase converts testosterone into estradiol, which can cause estrogen overload and testosterone deficiency.
* Too much free testosterone is being bound by SHBG (sex hormone binding globulin). This would be especially apparent if total testosterone levels were in the high normal range, while free testosterone was below the upper one-third range.
* The pituitary gland fails to secrete adequate amounts of luteinizing hormone (LH) to stimulate testicular production of testosterone. Total testosterone in this case would be in the bottom one-third to one-half range. (On LabCorp's scale, this would be a number below 241-500 ng/dL.)
* The testes have lost their ability to produce testosterone, despite adequate amounts of the testicular-stimulating luteinizing hormone. In this case, LH would be above normal, and total testosterone would in very low normal or below normal ranges.
* Inadequate amounts of DHEA are being produced in the body. (DHEA is a precursor hormone to tes-tosterone and estrogen) (250).
