Free T3Updated 3 months ago
What is free T3?
Free T3 (triiodothyronine) is the active form of thyroid hormone, crucial for regulating metabolism, heart function, digestion, muscle control, brain development, and bone maintenance. Unlike bound T3, free T3 can readily act on tissues.
Why is free T3 important?
Free T3 reflects thyroid health and abnormal levels can indicate thyroid disorders. High free T3 suggests hyperthyroidism, while low levels suggest hypothyroidism. SiPhox Health includes free T3 in its Thyroid+ panel to help assess thyroid function.
Understanding free T3 levels:
- Low: < 1.9 pg/mL
- Optimal: 3.2 – 3.9 pg/mL
- Normal: 1.9 – 4.4 pg/mL
- High: > 4.4 pg/mL
T3 levels peak in the early morning and drop by afternoon, so morning testing may better detect hypothyroidism.
Maintaining optimal free T3 levels:
- Diet: Reduce iodine and eat more cruciferous vegetables to lower high T3; increase calories and carbs if T3 is low.
- Lifestyle: Manage inflammation, reduce stress, and improve sleep to support T3 levels.
DISCLAIMER:
If you are concerned about free T3 levels always consult your physician.