Dr. Aaron Hartman uses a crude oil to gasoline analogy to explain why patients on levothyroxine still feel sick. The body must convert T4 into usable T3, but poor absorption leaves high circulating T4 and insufficient active hormone, causing fatigue and weight gain despite normal lab tests. Liquid formulations like Tirosint may work better than standard tablets.
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I mean, so I would say, look, like maybe for people who only have access to that class of meds, which is the vast majority of people, maybe if they have an oral absorption issue, Tirosint solution might be better than levothyroxine. But the big message here is, you know, and I kind of view it as, as gaslighting again, in, in part because levothyroxine is the generic form of these medications. Okay. We're thinking again, crude oil. We have to be able to take that crude oil and convert it into gasoline to make our body run for fu— it's our fuel, right? So levothyroxine's the crude oil, Synthroid, Tirosint, Levoxyl, Unithroid. Um, I left one out. I don't even remember which one, but they are all crude oil too. There's different nuances of branding and fillers, et cetera, but you're getting crude oil. So the worse you are at taking that crude oil, and making it into gasoline, number one, the worse you're gonna feel. You're going to have persistent symptoms because if you have a garage full of crude oil and your gas tank is on empty and you don't have a way to convert it, you're not going anywhere in your car. It's the same. You can take all the levothyroxine-based meds in the world. If you can't activate them, you're not go— you're not gonna function. You're gonna persistently have symptoms. And what really is fascinating, the worse you are at activating those medications, the better your labs look to a regular clinician. So you accumulate crude oil in your garage, you stockpile it, your T4, that sends a message back to your brain and it actually lowers your TSH. And so to a regular clinician who's just checking your TSH, oh gosh, this is what happened to me. You have plenty of thyroid hormone. In fact, maybe you have too much. We need to reduce your medication. Oh, well, let's look deeper. Let's check your free T4, which is the second most common lab that's checked. In, in medicine, what's gonna happen if you're a poor converter? You're gonna have a garage full of crude oil. You're gonna have plenty of it. Your levels are going to be high. And again, your clinician's gonna say, you have plenty of medication, you have plenty of thyroid hormone. This isn't a thyroid issue. Your fatigue, your weight gain, your hair loss, your dry skin, your lack of libido. It has to be something else.
