McCall McPherson explains why reverse T3 matters: it binds to T3 receptors but blocks them instead of activating them. Levothyroxine can be converted to reverse T3 instead of active T3, which is why a full thyroid panel should include TSH, free T4, free T3, and reverse T3.
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Why it is so important if you have a thyroid problem to be checking your reverse T3. This is like the most disregarded lab. And especially if you are on a medication like levothyroxine or Synthroid or tiroscent meds that are based in T4 or inactive hormone, you cannot ignore checking your reverse T3. So reverse T3, so you have an understanding, is shaped like T3, which is your active hormone. It's your most important hormone. It's what regulates your symptoms, your energy, your cognition, your metabolism, all the things. But it's shaped like T3 in reverse. That's why it's called reverse T3. Right. What that allows it to do is actually bind and land at the same landing spot as T3. But instead of activating that landing spot for, you know, energy creation, that kind of thing, it just sits there, blocks it, and doesn't let T3 bind. So what ends up happening is the higher your reverse T3 is, the lower T3 you actually are able to absorb. Okay. When you're on levothyroxine, Synthroid, tyrosine, all of those class of meds, it's all inactive hormone that actually, for many, many people, that hormone dumps into reverse T3. What we're hoping it does is that you take it and make it into T3 or your active hormone. That is not what's happening for most people. And that is why people still have thyroid symptoms. So they don't activate it, and to make the situation worse, they often take it, dump it to their inhibitory hormone. No one knows this because no one is checking reverse T3, and no one is checking T3 to see if you're actually able to ever activate your medication. So if you are on a thyroid medication like the ones I mentioned, get a full thyroid Panel, which is TSH, free T4, free T3, and reverse T3. So important. I hope that's helpful, y'.
