Thyroid Function
T3 (Triiodothyronine)
T3 is a thyroid hormone that plays an important role in your body's metabolic rate, heart and digestive functions, muscle control, brain development, and bone maintenance.
Why is it tested?
To diagnose hyperthyroidism or to monitor the effectiveness of treatment for a thyroid disorder.
What does a HIGH level mean?
- Hyperthyroidism
- Graves' disease
- Toxic nodular goiter
- High levels of proteins that bind T3
What does a LOW level mean?
- Hypothyroidism
- Hashimoto's thyroiditis
- Starvation or severe illness (euthyroid sick syndrome)
Normal Reference Range
80 to 200 ng/dL (Total T3)
*Ranges may vary slightly depending on the specific laboratory and testing methods used.
Related Biomarkers
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