What Is a TSH Lab Test? Decode the Thyroid Numbers Your Doctor Overlooked

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0:49Learn more at windows.com slash student offer. While supplies last, ends June 30th. Terms at aka.ms slash college PC. Brain fog could be due to low thyroid hormone or hypothyroidism. And when it comes to thyroid testing, most doctors are only testing a TSH, that's thyroid stimulating hormone, and that's not enough. So we're going to get into the exact labs and what the ideal parameter should be for those labs in today's episode. So what is TSH? TSH is a brain hormone that tells your thyroid to make thyroid hormone. And when we measure TSH, it's really a gauge of how loud your brain is talking to your thyroid.

1:29And the less your thyroid is responding, the louder that TSH is going to get. So the higher that number is going to get. So let's get into these lab ranges. And before we do that, hi, I'm Dr. Jolene Brighton, and you are listening to The Dr. Brighton Show. So here's what to look for on your thyroid panel. TSH ideally should be somewhere between 1 and 2.5. The lab range often goes up to 4.5, sometimes 5, sometimes 10, sometimes 15, but research shows that symptoms start long before that upper limit. If you are on a fertility journey, you're trying to get pregnant, we definitely want that TSH below 2.5.

2:07Now, if your TSH is above 2.5, but you have no symptoms, that doesn't mean that you are necessarily hypothyroid. This can be a transient in elevation, and we may need to retest in the future to confirm it. But when I'm running a thyroid panel, I'm also going to include a free T4. So free T4 is what your thyroid makes. Optimally, that's going to be about 1.2 to 1.8, and that is telling us how well your thyroid is responding to the TSH. So TSH says, hey, thyroid, make T4. Great. We know where that's at, but we need to know about the conversion to the active hormone, which is free T3. And we typically want to see that between 3 to 4.2.

2:50And again, sometimes these numbers are not in the ideal range, one-off, and you're not having symptoms. And we don't worry about that. We retest. Now, there's another test that sometimes I'll run called a reverse T3. This shows if your body is blocking T3 from doing its job. So optimally, we want to see that below 15 nanograms per deciliter. And we take that reverse T3 in conjunction with free T3 to understand, is your body converting it to active thyroid hormone? That free T3 is your mood, your menses, your metabolism, your gut motility, and how your brain works. We're going to get into that.

3:28Or is it pushing it into reverse T3, which I like to call the hibernation hormone because it literally makes you like a bear in winter because you are wanting to sleep. You're kind of cranky. You're very lethargic. You're trying to like store energy. It's not a great way to fill. And we know with reverse T3, that is often elevated when we are very stressed. If there has been something traumatic, like a car accident that we've been in, we can also see it elevated if we are sick. So again, when we look at thyroid labs, it is conjunction with your symptoms and how you feel. We're not going to just look at thyroid labs and treat that alone.

4:07We have to also take into account the human who's living in the body that's producing those kinds of labs. So let's talk about antibodies because the number one cause of hypothyroidism in the United States, in most developed countries, is Hashimoto's thyroiditis, which is an autoimmune condition in which your body makes antibodies. They tag the thyroid and then the rest of the immune system comes in and it destroys it. And if we destroy enough tissue, we have to go on a thyroid medication because we're no longer able to make the levels that we need. So what are we looking for in lab testing? TPO or thyroid peroxidase and TG, which is thyroglobulin antibodies.

4:49This tells us if your immune system is attacking your thyroid, known as Hashimoto's thyroiditis. So you can have these antibodies and not have symptoms. Usually we see the antibodies first. After enough tissue destruction, then we start having symptoms. Now, if you're currently on thyroid medication, we're going to talk about that today. But if you're on T4, like lipothyroxine, we look at free T3 and reverse T3 because that's how we know your body's actually converting the medication into what your brain can use, which is that free T3. And if you're not familiar with what the free hormones are, free T4 and free T3 is actually what's bioavailable, what your cells can use.

5:30If it's total, that's bound up. That doesn't tell us as much. And so I don't typically run those unless I have concerns about binding proteins. And then I may also run a thyroid binding globulin to understand if you're making enough hormone, but you're binding it all up. And we can see elevations in thyroid binding globulin with certain medications. So hormonal birth control is one of those. It's well documented that hormonal birth control can lead to elevations in thyroid binding lebulin, which may mean that if you're on it, like the pill, we have got to increase your thyroid hormone. We also see the same is true if you're taking oral estrogen for menopause hormone therapy.

6:11And it can also happen as well, depending on the hormone therapy being used if you're going through fertility treatment. So anytime we are giving estrogen or estrogen is going up, we may want to look at thyroid-binding globulin and look at the total hormones as well. But honestly, with the cost of labs and the considerations around that, usually running just the free hormones are enough. So free T3, free T4. So in this episode, we're going to talk exactly how and why low thyroid hormone leads to brain fog, plus the exact nutrients your thyroid needs to do its job right. But first, if this episode helps you understand your labs or if you've learned something already, pause for two seconds and leave me a quick review.

6:54It helps us reach more women who deserve real answers about their hormones and their brain health and get the support they need. So if you've already left a review, thank you so much. and let's get into how low thyroid hormone causes brain fog. Let's talk about what's actually happening in your brain. So when thyroid hormone is low, there's several key processes that go offline. So firstly, we've got reduced glucose metabolism. So your brain is very hungry for glucose. So your brain uses about 20 % of your body's total glucose. So when we say glucose, that's the sugar that's circulating in your bloodstream.

7:35So low thyroid hormone slows down that uptake and that means less energy. And less energy means slower thinking, memory struggles, like you don't feel as mentally sharp. This is why rain fog is one of the top symptoms of hypothyroidism. The second thing we see is decreased myelin production. Myelin is the insulation that keeps electrical signals between neurons sharp and fast. When thyroid hormones drop, this signal starts to slow down. And so your thoughts feel like they take longer and you start to begin feeling kind of fuzzy. Now, thyroid hormone is also involved with our neurotransmitters.

8:19So we can see low dopamine and serotonin synthesis. This is why hypothyroidism can also have the symptoms of depression. So thyroid hormones regulate enzymes involved in neurotransmitter production, and this is why hypothyroidism can mimic ADHD-like brain fog or depression. And so this is why for everybody listening, if there's potential diagnosis of ADHD, hypothyroidism is one of those things that needs to be ruled out. If someone is depressed, whether it's depression throughout the entire month, if they're having postpartum depression, if the depression even seems cyclical, I always make sure to check a thyroid hormone just in case.

9:01No one ever said you have to have one thing and you can have two things going on. But hypothyroidism is a very common cause of depression that does not respond to medication like SSRIs. And so I would submit rather than putting someone on SSRI immediately, of course, there's a time and a place to use medications, we always look at thyroid when a woman is presenting with depression because who gets hypothyroidism? Women primarily. Yes, men get it too, but women are the majority of the population that have autoimmune disease and have hypothyroidism. Another way in which hypothyroidism contributes to brain fog is by a mitochondria slowdown.

9:43So thyroid hormones stimulate your mitochondria. Those are your energy factories. And that means you're making less ATP. So less T3 means less ATP. ATP is the molecule your brain runs on. Interestingly, functional MRI studies have even shown reduced activity in the prefrontal cortex in untreated hypothyroidism. Prefrontal cortex is where all of your executive function and attention are based in. So that's like, the operational center there. So when you say, I feel like I'm losing my edge, it's not just in your head, okay? Well, it kind of is, right? Because it is your brain, but it's about the hormones and how they're affecting your brain.

10:28So I mentioned medications earlier on. I want to talk about medications because thyroid medications can be life-changing. When done right, you cannot live without thyroid hormone. I know there's a lot of people out there who are like, oh, you should try to never be on a medication. Yes, absolutely love that goal. But sometimes it's just not the cards you got dealt. Like I said, if you've had enough thyroid tissue destruction, you are going to require a medication because you no longer have enough of the gland to make enough thyroid hormone. You cannot live without thyroid hormone. It is a non-negotiable hormone.

11:06And I don't know why in the thyroid community, there are people who will shame you for using a medication, act like you didn't work hard enough, act like it's somehow your fault, and you should feel ashamed of having to leverage a medication. Let me just be really clear. Oftentimes when I see medical providers who do this, they don't have a license to actually prescribe. And if you don't have a license to prescribe, you don't have the education actually to advise on it because you don't have a license to prescribe, you're not allowed to prescribe, you never got pharmacology. So as a licensed healthcare provider who does prescribe thyroid hormone, I will tell you it can be absolutely life-changing.

11:45We only use it when it's absolutely necessary. And I really want, I've always said this so many times, but you cannot live without it. You will end up not just depressed, not just with brain fog, but you can end up with heart conditions that are not compatible with life. So if you need thyroid medication, it's a non-negotiable, but again, it has to be done right. And it's often not enough on its own. So we're going to talk about other things as well. So the most common prescription is levothyroxine. You'll see it as like synthroid, tyrosine. That is T4 only. And remember, T4 is the inactive form of thyroid hormone.

12:29So here's the issue with that when it comes to your brain fog. Your brain doesn't use T4. It uses T3, which is the active hormone. So some women have genetic variations or maybe they're struggling with nutrient deficiencies. We're going to talk a lot about nutrients today. Or maybe there's chronic inflammation and that's blocking the conversion of T4 to T3. So this is something we have to be aware of is that we can't just give T4 and assume that it's going to work for everyone. And T4 will make your TSH look normal, even though your brain cells are starving. So this is why it's really important to also look at that free T3.

13:10And that's why I gave you the lab values at the top of this. So there are alternatives. If people are not doing well with the T4 to T3 conversion, natural desiccated thyroid hormones, so like armor thyroid, NP thyroid, compounded options. We can also use a T3 like cytomel. We can add that in. So there are different options for people when it doesn't work to be on Synthroid alone. And studies show some patients experience better mood and focus and energy on a combination therapy compared to T4 alone. And this is where individualized medicine absolutely matters because there's no one size fits all thyroid dose.

13:54You have to treat the symptoms and the lab. So we do the lab testing and then we look at the person who's in front of us and that is what we are treating. But like I said, sometimes meds are not enough on their own. And a big reason for that is because Hashimoto's that I talked about, the TPO and thyroglobulin antibodies that we need to measure to evaluate for that. That's an autoimmune condition where your immune system attacks your thyroid tissue. It's the number one cause of hypothyroidism and it's highly inflammatory. So you can feel amplified brain fog because it's not just about the thyroid hormone, but it's about the neuroinflammation that can take place as well.

14:36And here's what most people don't realize. thyroid medication doesn't stop the autoimmune process. It replaces the hormone your thyroid can no longer make, but it doesn't calm the immune fire. So that's really important to understand because if we're treating Hashimoto's, we have to also look at what's driving the immune system. So if you have Hashimoto's, you're listening to this, you must address why your immune system is attacking your thyroid. So first place we always look is gut health. So about 70 %-ish of your immune system lives in your gut. If you have leaky gut or intestinal hyperpermeability, if you have infections or even just dysbiosis and imbalance in your gut flora, that can trigger thyroid antibodies.

15:20I'm going to link in the show notes to a couple of episodes. One of those is going to be all about gut health and hormones. Definitely take a listen to that. There's a lot of tips in there for what you can do about your gut health. Now, the other thing that can be going on with Hashimoto's is we've got nutrient deficiencies. So low zinc, selenium, vitamin D, those can worsen antibody production. Interestingly, there have been studies showing that myoinositol and selenium, those two can help put antibodies into remission along with nutrition and lifestyle. So this is in people who are deficient.

15:58The other thing we have to look at is blood sugar dysregulation. So insulin spikes, blood sugar spikes, that can drive inflammation. It can worsen autoimmune activity. It can cause more dysregulation in the HP access. So hypothalamic pituitary adrenal access and cortisol should be governing that inflammation in your body. But when we have blood sugar spikes and we have autoimmune disease, that can be a double hit to the HPA access. We also need to be looking at environmental toxins. So BPA, phthalates, heavy models, they can interfere with thyroid receptors. Some of the things that are in flame retardants, for example, or even found in our food supply like bromine, they can interfere with iodine because these are all halogens and they can compete for the same receptors.

16:47I will link in the show notes to a couple of articles about environmental toxins so you can know the steps to take. One thing I hear from women all the time is that they're struggling with symptoms like hot flashes, sleep disruptions, and brain fog, but aren't sure where to turn to for help. Menopause is inevitable, but suffering through it isn't. That's why I want to tell you about Alloy. Alloy is a digital health platform that connects you with a menopause specialized doctor who can create a personalized treatment plan tailored to your needs, all from the comfort of your home. Join the 95 % of women who tried Alloy and saw relief in the first two weeks.

17:29Head to myalloy.com and use the code Dr. Brighton. That's myalloy.com, M-Y-A-L-L-O-Y.com, and the code Dr. Brighton, D-R-B-R-I-G-H-T-E-N. Share your symptoms and you'll get a fully customized treatment plan and unlimited messaging with your doctor. Plus, you'll get$20 off your first order today. That's M-Y-A-L-L-O-Y.com, code Dr. Brighton. Chronic stress. So I alluded to the HPA access. if you have high cortisol, that can cause problems with immune system regulation, and it can block T4 to T3. So we definitely have to figure out what the stressors are, because it's not always psychological, it's not always mental, emotional.

18:21It can sometimes be stressors in your gut, other stressors causing chronic activation of the HPA axis. So the takeaway is that treating Hashimoto's means calming the immune system and looking at you holistically, not just your body, not just your habits, but also the environment that you're living in and making sure that we know what is driving Hashimoto's. And if you are going up, up, up on your thyroid medication, it is a very good sign that your autoimmune disease is not in control. And why does this matter? You know, a lot of doctors will act like, well, it doesn't matter with Hashimoto's because like we have thyroid medication and we'll just like replace it, accept that once you lose immune tolerance, so once your immune system doesn't understand that it's you and starts attacking your body, you can develop other autoimmune conditions.

19:13So it's really important that we get that autoimmune disease in check. Hashimoto's can also sometimes, although rare, lead to significant brain conditions. So significant inflammation of the brain, even degeneration of the brain. Again, rare, and this is why don't ignore your brain fog, okay? And it might be more than just your thyroid hormone, but it's really just important to understand that autoimmune disease makes people feel bad. Even if you can replace the thyroid hormone, we have to be addressing what's going on. Okay, I want to leave medications and go into nutrients because with my patients, whether they have Hashimoto's or not, whether they need a medication or not, we are always focused on the inputs that go into the thyroid factory.

19:59So think about your thyroid like a factory. It can only produce hormones if it has the right raw materials going in. We're going to go through a list of the things that need to be coming in. And the first one I want to start with is iodine, okay? You do need iodine, but you don't need too much of it. So iodine is needed to build thyroid hormone and the balance of it matters so, so much because if you have too much or too little, that can worsen autoimmunity. And I'm going to link an article in the show notes on exactly what you need to know that goes through the nuance of iodine, Hashimoto's, hypothyroidism, and what the research shows.

20:37Because some studies have shown when they introduce iodized salt into the population, they actually see increase in autoimmunity. So I'm going to link that for you and we'll move on to selenium. So selenium converts T4 into the active T3, and it protects your thyroid tissue from immune damage. We can find it in things like sardines, Brazil nuts, and eggs. So yes, we're going to talk about foods that you can be eating here too. And you can back this up. You can take notes, or you can head to the show notes, and you will find the transcript there. Zinc is another one that is so super, super important.

21:16So that helps with the conversion as well. It also helps with your immune balance. Oysters, pumpkin seeds, beef, these are great sources of zinc. Iron is one I get concerned about in menstruating females. If you're no longer menstruating and you become iron deficient, we're looking for like a GI bleed. Like where are you losing blood? But as we have our period every single month, we can be losing iron. And without it, your thyroid can't make hormones at all. So you need to check ferritin. I like to see that above 70. It has to be at least above 50, but 70 nanograms per milliliter for women with thyroid issues is much more ideal.

21:57We want to check ferritin because that's the storage form of iron. Your CBC, by the time you show anemia, you are tapped out on your storage, okay? You're tapped out on that ferritin. So ferritin can help me catch that earlier. Super, super important for women to be getting this checked regularly. I mentioned vitamin D earlier. Vitamin D helps regulate immune tolerance. It's critical, critical for Hashimoto's. Sunshine is your best bet. You can also find it in dairy products. If you take mushrooms, put them the gill side up out in the sun, they can generate some vitamin D. You can propagate your own vitamin D that way.

22:37And with vitamin D, I always like to see vitamin A as well. Vitamin A is essential for your thyroid hormone receptor sensitivity. So that helps your cells respond to thyroid hormone. You're going to find that in liver. Oh my God, like best source is definitely liver, but not everybody loves that. So egg yolks, cod liver oil. If you don't like liver, maybe go that route. Butter. So grass-fed butter, beta carotene rich veggies like sweet potatoes, carrots. Those are converted less efficiently. so animal sources are definitely more potent. Sometimes we also need to supplement with vitamin A, but I want you to understand vitamin A is super important for the receptor.

23:18We talked about TSH, what the brain says to the thyroid. Thyroid responds with T4. That goes out into circulation, gets converted to T3. You can make all of that great. Everything's going fine. Your receptors, maybe due to inflammation, maybe due to nutrient deficiencies, are not able to actually respond to that thyroid hormone. We can have receptor resistance. Just like we have insulin resistance, we can have thyroid hormone resistance. Super, super lame. Vitamin A is definitely one of those that can really help. And as I'm going through all of this, I have an anti-inflammatory meal plan, drbrighton.com slash plan.

23:54The plan talks a lot about perimenopause. It talks a lot about weight loss. Spoiler, the stuff that helps with weight loss actually helps with autoimmune disease as well. But if you need a guide to getting started in a nutrient-dense diet, anti-inflammatory recipes that are actually delicious, go grab that. I'll also link it in the show notes. I mentioned earlier how important blood sugar balance is. Chromium is a nutrient we want to think about for that. So that supports your blood sugar balance. It helps your cells use insulin efficiently. That helps stabilize thyroid hormone conversion. So chromium food sources, broccoli, green beans, whole grains, eggs, apples, shellfish, incorporating those to get that chromium up.

24:37That can also help with sugar cravings. As you optimize your blood sugar, you crave less sugar. And let's talk about riboflavin. So that's vitamin B2. That's needed for thyroid hormone production, for energy metabolism. You will find that in eggs, organ meats again. You might not like me for that. But it's also in almonds and yogurt, mushrooms, spinach. So there's lots of non-organ meat sources of that as well. But I mean, I bring up organ meats because they are the most nutrient-dense foods on the planet. But I get not everybody loves those. Manganese. We don't talk about this one a lot. We always talk about magnesium.

25:17Also important here, But manganese, it protects the thyroid from oxidative stress during hormone synthesis. So as your thyroid is doing its job and it supports enzyme activity in thyroid hormone production. Now you're going to find that in pineapple, oats, brown rice, pecans, hazelnuts, leafy green vegetables. If you don't want to do organ meats, then I just ask you eat leafy greens like every day because those are also very nutrient dense. Now, I want to talk about an herb called coleus. So this is not a nutrient, but it's an herb that supports cyclic AMP activity. That's a messenger that helps thyroid cells release the hormone.

26:04Now, you're not going to find this in any foods. This is an herb. You have to take it as a supplement or as a tincture. I actually have it in our thyroid support formula because it's a good ally on top of the nutrients that you're taking in. And speaking of nutrients, we should definitely talk about tyrosine. So tyrosine is the amino acid backbone of thyroid hormone T4 and T3. So your body literally builds hormones from tyrosine plus iodine. Iodine always gets talked about, but tyrosine is really important as well. And food sources, so you're looking at a lot of animal products like fish, chicken, turkey, eggs, dairy.

26:44But you can also get it in almonds, sesame seeds, pumpkin seeds, things like tempeh. So several food sources out there. If you're aiming to get your 30 grams of protein at every meal minimum, you're probably getting enough of this amino acid. So those are the nutrients we definitely want to be focusing on. And listen, if you've been told that your labs are normal, but you feel like something's not right, you should definitely investigate that. And you deserve a full thyroid panel. You deserve personalized treatment and a plan that supports both your thyroid and your brain. So by eating these nutrients, testing your thyroid, and treating appropriately, that can help you with increasing your energy, helping with your focus, helping get rid of the brain fog.

27:31And all of that starts with understanding your body and not fighting with it. I think especially for hypothyroidism women, it's really frustrating when you're gaining weight and you're cold and you have dry skin and you're losing hair and you're constipated and your doctor's like, you should just eat less and move more. And in reality, you don't need to be fighting with that. You need to be curious about that. You need to be asking, why do I have these symptoms going deeper? And the only way for us to really understand And what is going on with your thyroid is for us to test it. We have to do that full panel.