Reverse T3 is not the big bad wolf in our thyroid system. It is a necessary brake where FT3 is the gas pedal. We can get too much RT3 when we take more T4 medicine than we are able to convert to T3. Could be just too high dose, or that we don’t convert well. Other conditions can increase RT3 too much as well. It’s a good idea to test RT3 from time to time. But it is not necessary to test all the time.
I will look at myths and misunderstandings around RT3. for one thing, RT3 does not block T3 by occupying T3 receptors. Nor does it hinder T4 to T3 conversion. If there is a big bad wolf, it’s deiodinase 3, D3. It’s D3 who converts T4 to RT3, and who hinders T3 from attaching to the T3 receptors i the cell nucleus.
But there are no “wolves” in our thyroid system. Only participants with their own roles to play. And the better we understand the play, the more can we hopefully optimize our thyroid levels and feel better.
I will look at what causes too high RT3, and what one can do bring it down.