I recently put out a blog post that introduced an important new piece of research that shows that a suppressed TSH whilst on thyroid treatment does not mean that the patient is hyperthyroid.
The research shows that thyroidless (athyreotic) thyroid patients require enough T4 (Levothyroxine, Synthroid) medication to get their FT3 levels up high enough to feel well. When this happens TSH is suppressed. The research shows that TSH suppression on thyroid treatment does not mean the patient is hyperthyroid.
A person not on any thyroid treatment who has suppressed TSH could easily be hyperthyroid (unless they have a pituitary issue). But this situation is totally different and it has been applied to thyroid patients under treatment and used to keep many under-medicated.
Being thyroidless is just at one end of the spectrum of thyroid patients. Any thyroid patient requiring thyroid hormone treatment has some loss of thyroid hormones from their gland and may also need very low TSH in order to get well.
However, IF you accept that TSH can be suppressed in a thyroid patient on treatment (which you have to because the research is compelling), then the consequences of this are significant.
This means that on thyroid treatment, TSH could be anywhere from just inside the top of the lab range right down to near zero. Thyroid treatment might even need to be increased when TSH is suppressed in order to get a therapeutic response i.e. to eradicate a thyroid patient’s symptoms. This does not mean that the patient is hyperthyroid. It simply acknowledges that the person needs more T3 converted from T4 to feel well, i.e. enough of the actual active thyroid hormone.
Currently, the use of TSH is incorrectly being interpreted in the same way it is for an individual not on any thyroid treatment (and who may be genuinely hyperthyroid). It is incorrect and is being used in a manner likely to keep many thyroid patients under-medicated.
Ok, so where does that leave us in terms of knowing if a thyroid patient is properly treated?
The answer is “Nowhere” if TSH is the only measure!
TSH tells us very little other than the patient’s pituitary gland is responding correctly as the thyroid medication is increased. Being low in the range on TSH does not mean the patient is correctly treated with the right amount of thyroid medication or even the right type of thyroid medication!
The use of TSH to determine correct treatment level is flawed!
Doctors and endocrinologists are ultimately going to have to face up to the science and begin to ignore their sacred TSH. It is not the beacon of light onto the correct treatment level at all.
The logic of using TSH comes crashing down!
The house of cards collapses!
This has to happen at some point. Research findings and science cannot be ignored forever!