Thyroid
T3 Uptake
Unit: %ID: T008
What This Test Measures
Indirect measure of thyroid hormone binding proteins
Conventional vs. Functional Optimal Range
Conventional "Normal"
24-39 %Your doctor says you're "fine" anywhere in this range
Functional Optimal
27-37 %This is where you actually feel great
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
T3 Uptake is old-school but helps interpret Total T4. High uptake = more free hormone (hyperthyroid or low binding proteins). Low = more binding, less free hormone. Functional range keeps binding capacity optimal, not just "normal."
When This Test Is High
Low binding proteins (high T3 uptake), hyperthyroidism
When This Test Is Low
High binding proteins, hypothyroidism, high estrogen
Related Conditions
Hormone balance, protein binding capacity
Recommended Follow-Up
Check alongside Total T4; calculate Free Thyroxine Index if needed