Why do I want all these thyroid tests?


I wanted to take a few minutes, it's the end of the day here, and excuse the bare walls behind me, I'm in my new office, and we haven't had time to quite finish settling yet. First video from the new office so I guess that's a milestone.

                                           I've had a couple patients come in the past, probably two weeks, where they've had ... well, the patients haven't necessarily had questions about a full thyroid panel, but their other doctors have had questions about, why are we ordering all this lab work? Why would want all this lab work? What are you trying to prove? What are you looking for? What's the relevance of this?

                                           So I wanted to take a few minutes and do a video. I've done thyroid videos in the past, several of them, but I think it's about time I've done another one. So, that's what I'm doing here today.

                                           In a full functional medicine thyroid panel, we're generally looking at a TSH, a total T4, a free T4, a total T3, a free T3. In many cases we'll do a reverse T3, thyroid antibodies, and sometimes some thyroid binding globulin's. So, that's kind of a full thyroid panel. I usually add a vitamin D to it, sometimes we'll add an A1C to it, which is a marker for blood sugar. But in some cases we do it, in some cases we don't. But that's kind of full functional medicine thyroid panel.

                                           The question is, why do we need all that? Well, let me start by telling you what conventional doctors typically do, and why they do it, because I think it's important you understand the rationale. Your conventional doctors job is to diagnose hypothyroidism. Basically, a low functioning thyroid. A thyroid that's not producing enough T4, which is thyroxin. It's tyrosine, which is an amino acid, it's got four iodides attached to it. That's T4.

                                           The two ways they generally look at that. They will do what's called a TSH, or a thyroid stimulating hormone test, and they'll do some version of a T4 test, or thyroxin, like we talked about. Now, TSH stands for thyroid stimulating hormone. It's actually made by the pituitary, it's not made by the thyroid, and it's a hormone that places an order for thyroid hormone. It asks the pituitary, or tells the pituitary to make a certain amount of T4. The presumption is that if TSH is getting high, you don't have enough T4. That's why you're asking for so much. And that if TSH gets low, you've got too much T4, that's why you've quite asking for it. In many cases when people start taking a T4 medication, like Synthroid, Levothroid, Levothyroxine, something like that, as they take T4, their body doesn't see the need to ask for it and their TSH levels drop very low. On the flip side of that, if they aren't making enough T4 their TSH levels will get very high, and it's typically reliable, although, not all the time. As you'll see, I'm gonna lay out some patterns for you in a minute of functional thyroid issues that we see. But that's why they would look for TSH. It should run inverse to your T4 level. It's high, low T4. It's low, high T4.

                                           Looking at a T4 level allows you to confirm that. You can look at either a total T4, which is everything that the thyroid's producing, although it makes a little bit of T3, but all of the T4 the thyroid's producing, or you can look at what's called a free T4, which is only the part of the T4 that isn't bound to proteins that move it around the bloodstream. Once it binds to proteins and gets moved around, it's not really available. It has to be broken off those proteins and made available to go on to the next few steps of this process. That would be, the part that's broken off and available would be free T4, but the whole total would be total T4.

                                           Sometimes they'll do a TSH and a free T4, sometimes they'll do TSH and a total T4, and sometimes they just do a TSH. But those are all ways of conventionally accessing hypothyroidism. Now, if your only concern is whether or not the thyroid is producing T4 in an appropriate amount, you can make the argument that those are the only relevant tests. If the TSH is high, or the T4 is low, the doctor is gonna give the patient T4, everybody's happy, problem solved.

                                           But, typically the patient's not asking, "Am I low in T4?" Or, "Do I qualify as having the diagnosis of hypothyroidism?" The patient is saying, "Is there a problem with my thyroid hormones that could be causing me to feel the way I feel?" Or, "Contributing to my symptoms?" The list goes on. But that's generally more the question the patients are asking.

                                           From a functional medicine perspective, or from a functional wellness perspective, doctors will look at the whole supply chain, or the entire hormone cascade. We'll start with a TSH, same reason, we're looking at what the pituitary's asking for, we'll look at total T4 coming out of the thyroid, and then the unbound portion, which is the free T4. Then we look at total T3, which is what that free T4 turns into. There's an enzyme called five prime deiodinase. Removes one of the iodides from that T4, turns it into T3. So we look at total T3, same thing, a lot of it's gonna be bound to transport proteins in the blood, a small amount is not, that's called free T3. Free T3 is actual active thyroid hormone. That's the thyroid hormone that does everything thyroid hormone is touted to do. T4 is largely a transport form of thyroid hormone.

                                           I tell patients, if you by a book from Amazon, when it gets to your house, and it's still tapped up in the box, and in the shrink wrap, that's T4. You can't read it, but it's the book you ordered. Once you unpack it and take it out of the shrink wrap, now it's T3. You can open it and read it, it's usable.

                                           So, a lot of the symptoms patients have of not having enough thyroid hormone, thinning hair, cold hands and feet, weak nails, dry skin, constipation, poor libido, lack of motivation, brain fog, aches and pains, raising cholesterol ... I don't know if I mentioned fatigue or low energy, lack of motivation. Those all kind of go together as being a list of symptoms of not having enough thyroid hormone. Those come from not having enough T3.

                                           Now granted, if you don't make enough T4 chances are you don't have enough T3. But there are cases where you make enough T4 and still don't have enough T3. If you're looking at an entire thyroid hormone cascade you'll be able to see all the different steps, if you don't have enough T3 at the end of the day, you'll be able to look back and see where in this cascade did it go wrong. If TSH was good, T4 was good, total T4 was good, free T4 was good, and all of a sudden total T3 drops down below what's normal, well there's a problem between those two steps. Now you know where the problem is and all of those patients would be approached moderately differently.

                                           Antibodies. We look at antithyroid antibodies. Those are signs that your immune system is attacking your thyroid. You will always ... I had an argument from a doctor recently that once you see those antibodies once you never have to look at them again, you're always gonna have them, they're always gonna be positive. I don't disagree with that. But, you do need to understand that a clinical win, so to speak, according to research that's come out, probably in the last five years or so. If you can get those thyroid peroxidase antibodies, and we're talking about patients with Hashimoto's here, if you can get those thyroid peroxidase antibodies below 200, some research says below 150, but I think below 200 is probably a pretty good number. If you can get those antibodies below 200 you're really not doing much damage to the thyroid anymore. That's almost considered a clinical remission.

                                           But if all of a sudden they pop up to 600 or 800 again and they've been quietly sitting at 80 or 90 for a while, you've got to start asking yourself what's changed. Why is this patients immune system more aggressively attacking them? Do they have an illness? Did they recently take a medication? Did they change their diet? Are they going through a stressful period? Did they stop sleeping? What in the world is going on that's caused these antibodies to suddenly flare up? And likewise, if you're doing interventions, suggesting lifestyle changes, diet changes, let's say they get off gluten, something like that, and all of a sudden the antibodies calm down and they're below 200 somewhere, that's a clinical win. You've done something meaningful and you're going in the right direction.

                                           That's why it's important to check antibodies, I'd say at least annually, but, if you're doing a thyroid panel anyway, why not grab the antibodies and just see what's going on in that respect. I don't think it's a one and done kind of test.

                                           Normal ranges, let's talk about that, that comes up regularly. The normal ranges for Quest, Lab Corp, CPL, something like that, those come mostly from a nurses health study that was done, I don't know, a couple decades ago I suppose, and they tried to weed out hypothyroidism patients and then they took the patients that didn't fall into the category and did a bell curve of their results and took two standard deviations from the mean, that's all statistical gobbledy stuff. But basically, they took the middle chunk of those people and said that's gonna be normal. There have been several articles since then that have kind rebutted that and said that they didn't think they properly screened, they don't think they got all of those hypothyroid patients out. They've done other studies on other populations of people and said that those normal ranges should probably be considerably more narrow. Many of you that are my patients know that in functional medicine we use different ranges for those. You can go back to other videos and see them. I'll probably mention a couple of them as we go through.

                                           TSH for example, we normally look for it to be 1.8 to 3. Many references now say 1 to 2.5 or 1.5 or 2.5 would be a normal range for a TSH. Total T4 for example, 6 to 12 is kind of what we look for for that. But the ... our normal ranges tend to be a little bit narrower, and that's just a functional medicine thing. It's more about what's physiologically appropriate and less about what's been found statistically. Statistics are gonna compare you to an average population, and any of you that have been out and about in public lately and looked at the average population probably know that's not what you're aiming for. Okay, so that's ranges. They've been challenged, they haven't been changed yet, and that's why some doctors use different ranges then the labs have. But simply accepting the labs ranges as normal I think is a misunderstanding of how those ranges were developed.

                                           So, a couple of patterns that we can see that, as I explain them, you'll see why a full thyroid panel is pretty important. First of all there's primary hypothyroidism. That ... this is a basic test that the conventional doctors do for hypothyroidism. You are simply trying to find out if the thyroid is incapable of producing T4 at an appropriate level. That's primary hypothyroidism. Remember hypo is low, hyper is high. So, primary hypothyroidism, that's the main thing everybody talks about.

                                           Beyond that, you can have kind of a ... well, I'm gonna talk about under conversion next because I think that's the next most common thing that is seen in a functional practice. Where your TSH is normal, you're asking for a good amount, you produce a decent amount of total T4, you have a decent amount of free T4 ready to move on to the next stage, which is going into the liver and the intestines and a few peripheral tissues. But then when it comes out of that next phase and it's been converted into T3, all of a sudden the level's low. You aren't converting properly to T3. Again, liver and intestines are the biggest culprits there. You have to start looking at those organs and see what's going on.

                                           Now, that's not a thyroid problem, it's a liver or intestinal problem. It's a nutritional problem. It can be related to stress and inflammation, sometimes even blood sugar issues can slow that conversion. That's not a thyroid problem. So, if your doctor's looking for a thyroid problem, conversion isn't on their radar. It's not a thyroid problem. But it may leave you with a smaller amount of thyroid hormone then you need to feel good. Because what comes out of that conversion is T3, total T3, and then a small amount of that is free T3, that's real thyroid hormone. So, if everything's normal down to conversion, and you under convert, you don't have enough T3, you don't feel like you have enough thyroid hormone, that whole list of symptoms I blurted out earlier, you would have a fare amount of those. Alright, that's under conversion.

                                           You can see a pituitary based hypothyroidism where the thyroid is perfectly capable but the pituitary's not asking for much. So when it doesn't make enough TSH, the thyroid doesn't respond. Like, if you went into your boss at work and said, "Oh look, I only want one dollar an hour," and the boss says, "Okay, I'll give you a dollar an hour." You don't have enough money to pay your bills, but it's not the bosses problem, you didn't ask for much. That would be a pituitary based hypothyroidism. Thyroid's not making enough, but it's not the thyroid's problem, it's fine, that's a pituitary issue, a signaling issue.

                                           You can also have a signaling issue above the pituitary. Now, we do have something in play here called an HPT axis, hypothalamic pituitary thyroid axis. That's where the communication goes.  Hypothalamus releases something called thyrotropin-releasing hormone, TRH, that goes to the pituitary, tells it to make TSH, that goes to the thyroid, tells it to make T4. If the hypothalamus isn't making enough TRH, pituitary's not gonna do its job, thyroid's not gonna do its job. That's true at the end of the day, you don't have enough thyroid hormone, but it's not a primary thyroid problem, that's a hypothalamus problem. That could be caused, oh my gosh, leptin resistance, people that have certain eating problems, blood sugar problems, cortisol issues, inflammation, high insulin, and that can be even people whose blood sugar is well controlled because they're taking a lot of insulin. That high insulin level can affect the hypothalamus, you don't make enough TRH, that goes all the way downstream, you don't have enough thyroid hormone at the end of the day. That's another pattern. I would call it an upstream pattern, or an axis problem, a communication problem. So, pituitary can signal poorly. Hypothalamus can signal poorly.

                                           You can have ... you can have too many binders. Thyroid binding globulin, I mentioned that in the first list of tests. Sometimes what you see is the total amounts of hormones, like total T4 or total T3. That those are pretty appropriate, but the levels of free hormone are very low, or too low, at least. What that means is, you have so many binders holding on to that total T4 or T3 that too small of any amount is unbound and able to go onto the next step. Again, not a thyroid problem. This is happening outside the thyroid.

                                           Why are you making so many binders? Sometimes estrogen does that, when you have estrogen dominance, forces you to make more thyroid globulin, binding proteins. They bind up the thyroid, you have a hypothyroidism because you don't have enough hormone, but the thyroid's producing a normal amount. You see how that wouldn't be diagnosable as a thyroid problem but it's definitely a problem with thyroid hormone that would make you experience all the symptoms of not having enough thyroid hormone. That's the patient that says, "I swear I have hypothyroidism. I've read the questionnaires, I've filled them out, I checked every single box, I know I've got it," and the doctor does a TSH and says, "No, you're normal, it's not your problem." Well, if TSH is normal, T4's normal, but all that's bound up to these proteins in the blood and none of it's available, that is exactly your problem, it just isn't coming from the thyroid.

                                           Then sometimes we do have times where the actual cells don't allow thyroid hormone to come in very well. Just like you can become insulin resistant and leptin resistant, you can become resistant to thyroid hormone, and again, that's kind of a high cortisol, inflammatory, regulated, type of situation. With those types of patterns, hopefully you can understand why more then a standard thyroid panel would be important. More then just a TSH or T4 would be important.

                                           So, if you end up going to your doctor and they do a TSH or a T4 and they say, "No, everything's fine," but you swear there's an issue, don't be afraid to push for more thyroid testing. There's a book out recently by Isabella Wentz, W-e-n-t-z, I think she's a PhD Pharmacist. Does a great job going over thyroid hormone cascades and some of these players in this game. There's an older book by Datis Kharrazian, just look for Datis, D-a-t-i-s. Don't try to spell Kharrazian. I think the title is something along the lines of, Why Do I Feel So Bad When My Thyroid Tests Are Normal? Something along those lines. Kind of a red and gray cover with a lady looking exasperated on it. That's another good book about thyroid hormone cascade, why it goes beyond TSH and T4.

                                           Then, along with this, I mentioned a couple times in here, looking at things like hemoglobin A1C, blood sugar issues, insulin issues. When I run an annual physical panel on people, we look at things like fasting insulin, we look at blood sugar several different ways, we look at iron deficiency, we look at anemia problems. We look at inflammatory issues, we look at liver and kidney function, along with the full thyroid panel, because those things come into play when you're looking at the balance of thyroid hormone or what's effecting thyroid hormone, or if you want to rule out thyroid hormone as a problem all together. It's not as simple as just a TSH and a T4.

                                           Don't expect your conventional doctor to, I don't want to say buy into this, don't expect them to jump on this because their job is different. Their job is to diagnose hypothyroidism and what you need for that is a TSH, maybe a T4. When you look at the clinical requirements to diagnose hypothyroidism, that's it, and I think they have a very legitimate argument that if that's their job, why would do they all these other tests. But when you go to a functional wellness, functional medicine, nutrition based, integrative practice kind of situation, they're more likely to say, "Yeah, I know those problems can exist, but it can go well beyond that. Why do you feel the way you do?" If we think thyroid may be involved or if we want to rule it out, we're gonna run a whole panel of tests, look at the entire cascade, start to finish, and then tell you whether or not that's part of your issue and look for one of the patterns that I described.

                                           So, I wanted to let you know that that's why we do, as a functional medicine practitioner, that's why we do full thyroid panels. That's why we look at more then just TSH and T4.

                                           If you have questions, I know I spoke quickly, if you have questions, go below the video, put in your questions, I'll do my best to answer them over the weekend, and lets start a discussion because lots of you have different experiences with thyroid testing, thyroid medications, whether or not they're working, what you've been told. Let's just get it out there and we'll talk about it and we'll kind of clear the air and that way everybody gets a nice forum to discuss it. Okay.

                                           That's it for today. It's Thursday evening, hope you guys have a good weekend this weekend. I hope the weather's nice where you are. Until we talk next time remember, eat for you health, train for performance, and live the life you love today.

                                           Thanks for watching. I'll see you soon.


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