Why Your Thyroid Labs Look “Normal” but You Still Feel Off
The 7 levels of thyroid dysfunction, how to spot them in your labs, and the exact next steps to fix them.
Most people only test TSH, sometimes T4 and T3. That’s like checking your fuel gauge while ignoring the engine, spark plugs, and exhaust. You’ll never know why your thyroid isn’t working if you only look at one or two markers.
Thyroid dysfunction can happen at multiple levels:
TSH production – pituitary signal that tells the thyroid to produce hormones.
Hormone synthesis – thyroid gland making T4 and T3.
Conversion – turning inactive T4 into active T3 (or shunting into rT3).
Transport – thyroid hormones bound to proteins vs free and available.
Cellular uptake – whether T3 actually enters the cell.
Receptor sensitivity – whether receptors respond once T3 binds.
Immune interference – antibodies damaging enzymes, precursors, or receptors.
The symptoms (fatigue, low mood, stubborn fat, cold extremities, brain fog) are the same no matter where the block is — but the solution depends on the exact level that’s broken.
In this article I’m going to show you what each mean, how to interpret the results and then a step by step guide on what to do based on optimizing each, whatever your numbers or ratios might be.
Let’s get into it!
Step 1: The Essential Thyroid Panel
If you only test TSH, you’re playing with 10% of the picture. A full thyroid panel gives you the entire map:
TSH – pituitary signal.
Total and Free T4 – inactive storage hormone.
Total and Free T3 – active thyroid hormone.
Reverse T3 (rT3) – inactive blocker that competes with T3.
T3 Resin Uptake – shows how effectively T3 binds and enters cells.
Thyroid antibodies (TPOAb, TgAb, TRAb) – reveal immune attacks on thyroid enzymes, precursors, or receptors.
This panel tells you where in the chain the problem lies — signal, production, conversion, binding, uptake, receptor, or immune. Without it, you’re shooting in the dark.
A budget-friendly version of this is (which is what I do routinely):
TSH
Free T3
Cholesterol
I recommend testing extensively to see what’s wrong and what’s not and then only keep testing the few markers that were off and that you’d like to improve.
And then you measure body temperature and heart rate and look at other markers influenced by thyroid function, like cold hands and feet, dry skin, slow transit, shallow sleep, etc.