Free T3
What This Test Measures
Active thyroid hormone; metabolically active form
Conventional vs. Functional Optimal Range
The gap between these ranges is why you feel terrible with "normal" labs. Conventional medicine waits for disease. Functional medicine optimizes for health.
Gabriel's Take
Free T3 is THE active thyroid hormone that runs your metabolism. Gabriel's optimal band is 3.3-3.7 pg/mL. Below 3.3, even if "normal," can come with fatigue, weight resistance, and cold extremities, and it often reflects under-eating, illness, or liver or kidney disease, so look there first. The window is narrow, so judge the trend, not one value. This is where you actually FEEL the difference.
When This Test Is High
Hyperthyroidism, T3 overmedication, thyrotoxicosis
When This Test Is Low
Hypothyroidism, poor T4-to-T3 conversion, chronic stress
Related Conditions
Energy, metabolism, brain function, mitochondrial health
Recommended Follow-Up
Check Reverse T3, cortisol, nutrients (selenium, zinc, iron)