T7 Free Thyroxine Index (FTI)
T7 Free Thyroxine Index (FTI) is a clinical biomarker on the Thyroid panel, reported in ratio. Standard reference range: 1.2–4.9 ratio. Functional (optimal) range used by integrative practitioners: 2.7–3.6 ratio.
What is T7 Free Thyroxine Index (FTI)?
The Free Thyroxine Index (T7, FTI) is calculated from Total T4 and T3 uptake to estimate biologically active thyroid hormone when direct Free T4 measurement is unavailable.
Reference ranges
| Range type | Value (ratio) | Source |
|---|---|---|
| Standard (lab) | 1.2–4.9 | Typical Quest / LabCorp adult reference |
| Functional (optimal) | 2.7–3.6 | Integrative / functional medicine consensus |
How SomaVue interprets T7 Free Thyroxine Index (FTI)
SomaVue maps every result for T7 Free Thyroxine Index (FTI) against four clinical lenses — nutrient cofactors, toxin exposure, infection drivers, and circadian/hormonal context — and connects each interpretation to specific peer-reviewed citations. Pre-mapped clinical reasoning and cross-marker pattern detection are available inside the practitioner workspace.
See the full interpretation
Upload a patient PDF or enter values manually to see the four-lens analysis, cross-marker patterns, and cited evidence for T7 Free Thyroxine Index (FTI) and 205 other markers.
Try it freeEducational reference only. Reference ranges vary by laboratory, assay method, age, sex, and clinical context. Functional ranges represent integrative-medicine consensus and are not regulatory thresholds. SomaVue does not diagnose, treat, mitigate, or prevent disease. Always consult a licensed healthcare provider.