Free Testosterone
Hormone markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Free Testosterone values sit together on one chart and you walk into your next appointment prepared.
What is Free Testosterone?
The small fraction of testosterone circulating unbound to proteins, so it is freely available for your body to use.
Most testosterone in your blood is attached to proteins like SHBG and albumin; free testosterone is the portion that is not bound and can act on your tissues. Because total testosterone can look normal even when the active free portion is off, this test can help clarify symptoms. In men, lower free testosterone can be associated with low sex drive, fatigue, or reduced muscle and bone strength; in women, higher levels can be associated with conditions such as PCOS. Results are interpreted differently by sex and age, and a single value is not a diagnosis.
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References
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