Measures the Free, unbound triiodothyronine (T3) levels in the body. Free T3 measures the active available amount of T3 in the body.
T3 is a thyroid hormone. The thyroid plays a large role in regulating the body’s metabolic activity. Total T3 measures all the T3 in the body where Free T3 represents the usable T3 in the body. Low levels of Free T3 may indicate hypothyroidism (underactive) and elevated levels of Free T3 may indicate hyperthyroidism (overactive).
Is Fasting Required? No
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