Thyroid Questions - What's it do, how does it misfunction, what do we do?

Hey, it's Dr. A. The question I'm gonna talk about today is probably the most common thing talked about clinically, at least in general practice, when it comes to the average complaints around fatigue and other types of medical complaints, and that's thyroid problems. Many, many people have thyroid problems. Most people have low thyroid or hypothyroid, but there are some people that have a high or overactive thyroid problem. Then, of course, there's thyroid cancer, and that's a topic for another day. But it's important to understand if you are thinking about why a thyroid problem would create all of the various symptoms inside of you or whoever has it, what is the thyroid doing? Well, thyroid's a hormone, and it's structurally a little bit different than your steroid hormones, but it's still a hormone, meaning it goes and it binds to a receptor. It causes activity. Now, the thyroid does something very unique in that it actually works both on the outside of the cell in a small manner, and then in 2 places inside the cell. Inside the cell is really where you understand what the thyroid does. So first, it binds to the mitochondria, which create the energy for your cell. So you're literally— your metabolic rate is predicted by the level of thyroid that's going on. Okay. Now, like almost all hormones that are produced throughout the day, your body is producing it, and then as the levels go up, the signals to your brain that go from the brain to the thyroid stop going and saying, make more, and so the levels go down. Then the signals go out, make some more. The thyroid is right in your throat, so it's not a big trip, and they go all over the body. So So you have this kind of steady state. Well, you can either have too much or you can have too little. And if you think about too little of your metabolism, what's that gonna do? It's gonna slow everything down. So people will start to gain weight, they will feel cold, they can get dry skin, their hair can fall out, all kinds of things that are related to your normal metabolism can go on because your metabolism has slowed down. But the other important thing that the thyroid does, which is similar to some of the steroid hormones, is in addition to the mitochondria and your metabolism, it also goes and activates receptors in the nucleus of your cell. So literal nuclear receptor activation, just like a steroid might. And so in addition to keeping the machinery of the energy production in the cell going, it is also keeping the, whatever the business of that cell is going. So this leads to other problems that can occur. So if you think about the nucleus, that's responsible for proper cell division, But also it's responsible for the job of that cell. So if the job of that cell is a brain cell, the brain cell literally may slow down in its activity. If the job of that cell is to produce other hormones, that cell may not produce hormones like it's supposed to. And this is why when you get thyroid that is low, you can have many other systems in your body that are affected. It's a very, very core function in the body. Now, there's a couple of things to think about. The most common type of thyroid problem is low thyroid or hypo, and the most common form of that is called Hashimoto's thyroiditis, which is an autoimmune thyroiditis, and literally the immune system has decided to attack the thyroid where it actually synthesizes the thyroid hormone, and it attacks it in a couple of different places usually. Those attack points are areas that we can test in lab tests. So you hear about maybe someone checked your thyroid antibodies, which is generally how they would diagnose the Hashimoto's for the autoimmune part. Those are the antibodies that your body built up against you and your thyroid, but it's really against particular places inside the thyroid where you're making thyroid hormone. So you can imagine if your immune system is going into your thyroid and attacking synthetic points where you might be normally making thyroid, you're going to slow down your production of thyroid in most cases. Some people in the beginning will actually go a little high, but then they'll slow down. There's also a non-autoimmune hypothyroidism, and then there's a hyperthyroidism where everything goes faster. Well, I told you what thyroid did. Imagine if you have too much of it. Your heart rate can go very high. In fact, it can be very dangerous for your heart. You can lose weight without trying, which is usually never a good sign if you're losing weight without trying. You can be shaky, you can have sleep problems. So instead of a low metabolism, your metabolism's super high. Now you might think that that's a good thing, right, if you feel like you have a slow metabolism. And I have had people come in and they didn't seek medical attention until they'd lost about 15 pounds. And they said, well, I knew there was something wrong, but I just enjoyed losing the weight without really trying. Well, here's the problem. If your thyroid is going too high and you're getting these symptoms, I always tell people it's sort of like way too much caffeine, only to an extreme level. If your thyroid is going too high and you're having all that happen, it's not just that you're losing weight and maybe not sleeping and you're a little shaky. The big problem is your heart has the most mitochondrial density in your whole body, And so imagine if you have too much thyroid and you have all those mitochondria in your heart putting out extra energy, your heart can develop rhythm problems, you can develop tachycardia, fast heartbeat, hypertension, all sorts of stuff. And so when you're treating high thyroid, it's not a benign problem, it's a very big danger to the heart. So usually when we treat high thyroid problems, we do a couple of things. One is to give something to protect the cardiac muscle. Okay. Because we don't want that to go bad, and then the other is to do something to calm down the thyroid. But far and away, most thyroid problems are low. There are high, but those are usually fairly obvious. Now, you may go to your doctor and not have symptoms, and they might just annually do a screening, and that might be called TSH, thyroid stimulating hormone. That is the hormone that is released from the pituitary that goes and literally stimulates the thyroid to do and make what it needs to make. Traditionally, classically, if you are low thyroid, the TSH will just keep going up because the brain keeps telling the thyroid, you know, work, and the thyroid's not working hard, and so it keeps sending more TSH. If you have a hyperthyroid state, usually it will go the other way, okay? Now, in testing, the TSH is a screening measure, but you can also now test the T4 and the T3 hormones. So thyroid has a number of— there's T1 and 2 and 3 and 4, because that's the way the hormone is synthesized, but the ones that we measure generally are 3 and 4. T4 is the most produced hormone, and it is a prohormone, meaning it needs to be activated to work, and it's activated actually to T3. So what does the 3 and the 4 mean? What happens is inside of your cells and also in your liver for export, there is an enzyme called 5'-deiodinase, and it takes one of the iodines off. And so it goes from 4 iodines to 3. Why is that a big deal? Well, the 3-iodine molecule is active thyroid, and it will bind then to those receptors at the mitochondria and the— Okay. cell membrane and also at the nucleus. So in many people nowadays, if the TSH is not extremely telling and they have a lot of symptoms, it's very common to measure T3 and T4 so that you can see if your production is truly, you know, really trending downward, and certainly in hyper or high cases, you'll see that those are quite high. I mentioned antibodies. The other thing that is measured in folks, because Hashimoto's is an autoimmune condition, we can measure the antibodies. When people are having problems and again their labs are not looking quite right, they have a lot of symptoms, it's usually wise to measure the antibodies because sometimes the antibody attack that you can measure in the blood, those levels will go higher, which you don't want. Okay. You'll see those levels go up before the TSH starts to drop, so you can catch an early Hashimoto's patient that way. Now, for monitoring, it depends kind of what thyroid you're using and taking. Sometimes they'll just do the TSH or TSH and the T4, or sometimes if you have a complex case, you might get all of those things checked periodically, and that's really up to you and your doctor and how well your case is being managed. There's different prescriptions for thyroid problems, but generally they're analogs of the T4 or the T3 hormone or a mixture, and the most common used is a T4 hormone analog, meaning it looks just like the T4 that your body makes. So this would be levothyroxine, and there's a few trade names and things, but that's very common. To give levothyroxine, the idea being that the body has that deiodinase enzyme operating and it'll make the T3 out of it. In some people, we have to give T3 directly, and that's called levothyroxine, and that is an analog of the T3 molecule, and that one is a little bit goes a long way for most people. Now, people sometimes develop autoimmune resistance where the thyroid receptors get sluggish, sometimes that T3 will be used to break through the sluggishness, but again, that's between you and your doctor to sort all of that out. Sometimes there's combination products. The very first thyroid drugs that were ever available were made from pig thyroids where the hormones were extracted from there, and then they started using cows and pigs, and what you got there was a thyroid that was gland-based, but it still had hormones in it, and it had a mixture of T4 and T3 like your thyroid would normally. They were replaced by synthetic thyroid or analog thyroid, T3s and the T4s I talked about, a number of decades ago actually, but all of those are still generally available. And then sometimes your doctor, if it's a real complex case, might have a pharmacy make the 2, T3 and T4, together, or may just prescribe you a bottle of T4 at a certain dose and T3 because your body does better with that. Now, like we talked about in our taking pills session that we did, thyroid's one of those that's kind of fragile, and you're told to take it on an empty stomach. It's really very well tolerated. You can just drink some water with it. It'll digest. It tends to bind to other things very easily, especially minerals and things. So if you were to take your thyroid with, you know, milk or with any— most things have minerals, but anything that had minerals, it would tend to stick to it instead of absorbing like it's supposed to. So we usually have people take it right when they first wake up. Well, I'm Dr. A, and that is everything you wanted to know about thyroid in 12 minutes. And we'll be back for another session with other questions that have been asked. Thanks a lot.