Hormones & Performance·Best seller
Amenorrhea Profile
View
Hormones & Performance·Best seller
Free T3
Free T3 is the active thyroid hormone—the one that actually hits your cells and turns up metabolism, energy, fat-burning, and brain function. It’s converted from T4 and is far more powerful. Low Free T3 is one of the most common patterns behind fatigue, weight gain, brain fog, and cold intolerance, especially in high-stress or under-recovery states. It’s your real-world metabolic throttle.
- Unit
- pg/mL
- Health impacts
- Metabolic Health · Energy
In your dashboard
Your trend, against your optimal range.
Example data · how your trend would appear once you test
At every level
What we'd do at any value.
Exploring
3.70pg/mL
LowOptimal 3.20–4.20High
In your optimal zone
Habits that hold this position.
No specific guidance for this zone yet. We're working on it and will update this soon.
Order a test
Pick the lab that fits your day.
LabCorpTest code: 010389$39
QuestTest code: 34429$39
BioreferenceTest code: 0271-7$39
Keep exploring