You have been exhausted for months. Not the kind of tired a good night of sleep fixes. Hair in the shower drain, weight that will not move no matter how carefully you eat. You finally tell your doctor you think something is wrong with your thyroid, they run a test, and they call back to say everything looks normal. Then you sit there wondering whether you imagined it.

In this episode, Rachel explains what that one test actually measured and what it could not see. TSH is the signal your brain sends to your thyroid, not a measure of what your thyroid does with it. Checking only TSH is like checking whether the gas pedal is being pressed and calling the car fine. The pedal is moving, so officially the car runs.

What you'll hear:

- Why "normal" reference ranges are built on population averages rather than optimal function, and why a ...