Despite a normal TSH, some thyroid patients will fall far below their healthy set point for Free T3, the active thyroid hormone.
TSH behaves differently in thyroid patients.
TSH cannot indicate T3 sufficiency in thyroid therapy.
Source of graph:
Hoermann, R., Midgley, J. E. M., Larisch, R., & Dietrich, J. W. (2016). Relational Stability in the Expression of Normality, Variation, and Control of Thyroid Function. Frontiers in Endocrinology, 7. https://doi.org/10.3389/fendo.2016.00142
Therapy for hypothyroidism is supposed to remove the problem of low thyroid hormone levels. Instead, this phenomenon, as shown in the graph, is what it usually does to our levels of the most active, most essential thyroid hormone, T3.
The TSH-T3 relationship is distorted. We have to access lower levels of TSH in order to raise Free T3 to levels equal to or higher than the average in healthy controls.
In other words, the standard T4 medication (Synthroid) makes optimal “Free T3” levels hard to obtain without suppression of the pituitary TSH hormone (thyroid stimulating hormone).
For some patients who do not convert T4 to T3 efficiently, it is impossible to obtain optimized Free T3 on the standard monotherapy.
Raising the T4 dose won’t necessarily raise FT3 levels. Raising the dose will make T4-T3 conversion less efficient for such a patient (the body tries to inactivate T4 when it is above normal). It will also suppress TSH below reference range.
Some of us need to take T3 hormone to raise our T3. That will more powerfully suppress the TSH due to the “T3-dosing effect” on the hypothalamus and pituitary.
But here’s the thing — thyroid patients are forbidden to enter the realm of TSH suppression. Why? due to non-evidence-based fearmongering about Low TSH and health risk. No causation has been established between low TSH and these disorders, but we are still forbidden from suppressing TSH in order to raise Free T3 through medication.
The twisted goal of modern thyroid therapy is now TSH normalization, not T3 optimization.
Fixing hypoTHYROIDism is supposed to be about fixing low THYROID hormone levels.
But instead of treating our low thyroid hormone levels, our pituitary hormone, is being medically regulated to fit within HEALTHY people’s normal TSH range.
Why is TSH the target? Our TSH is not the problem. Abnormal TSH is not the cause of either hypothyroidism or hyperthyroidism.
They say our hypothyroidism has been “biochemically corrected” whenever TSH is in the statistical range. But our thyroid hormone levels are NOT corrected if our Free T3 is lower than it should be. Normalizing TSH does not fix FT3.
Why should the TSH test result the ONLY judge of appropriate dose and type of thyroid hormone medication?
As you can see in the graph, TSH is not in control of our T3 levels anymore. In thyroid therapy, abnormal TSH is now the price of obtaining normal FT3.
Without a thyroid gland to stimulate, TSH is impotent in doing its biological job. It is unable to give us any increase in either T4 or T3 hormone when we need it.
What is the point of keeping TSH in range other than to satisfy the medical system while our bodies starve from low T3?
This is the slavery of modern hypothyroid therapy.
TSH testing is not enough.
Test T3. Treat T3. Set us free.