Are you diabetic or hypothyroid? Interaction between thyroid hormone and HbA1c


All right. Today, happy Tuesday, by the way. By this time next week, Christmas will be done. I have a hard time believing that we're actually that close to Christmas. It's 70-something degrees and dreary here in Houston and just doesn't feel at all like Christmas, but Merry almost Christmas.

       Today, I'm going to talk a little bit, as you can tell from the title, about blood sugar and hypothyroidism. Article came out in the January/February issue of the Indian Journal of Endocrinology and Metabolism. The code for it, if you want to look it up on PubMed, the PMC code is 5240076. In this article, they do a good job explaining it. It's a long article, but the actual takeaway from it is fairly short. They took a bunch of people, random, through some testing and basically found that people with a lower thyroid hormone level, people that qualified has hypothyroid, had higher hemoglobin A1cs.

       Let me talk to you a minute about what a hemoglobin A1c is. Some of you are very familiar with it. It's abbreviated HbA1c. It's called hemoglobin A1c, glycated hemoglobin, glycosylated hemoglobin. Those are all the same tests, and this is a test that's done to monitor blood sugar over a longer period of time. They do an HbA1c, and you get a 90-day view or a 3-month overview of what blood sugar has been running. The basics of the test, if I were to explain this in various, over-simplistic terms, they're looking at red blood cells, and they're looking at what percentage of the red blood cells are basically sugarcoated. Think of taking a red blood cell and dipping it in sugar and now it looks like a glazed donut, so to speak, but it's a red blood cell. They're looking at the percentage of red blood cells that are glycosylated or glycated, which means they've been affected by sugar like that. That happens to red blood cells when your blood sugar gets high enough that it's likely a problem.

        When you look at the percentage of red blood cells that are glycated, you get a sense of how poorly controlled someone's blood sugar is. A normal number is going to be below 5.7, 5.7%. Less than that 5.6 or down to probably closer to 4, that's a normal range for that. Once you get closer to 6%, 6.2, 6.3, and 6.5, you're at really high risk of developing type 2 diabetes. We assume that blood sugar is getting out of control more and more frequently. We know you're not sensitive to your insulin. You're developing metabolic syndrome, prediabetes, call it what you like, but you've got insulin resistance or insulin insensitivity.

         Once you get above 6.5, you basically got type 2 diabetes. That's just how it works, and an uncontrolled type 2 diabetic can be at 7-1/2 or 8-1/2. I've seen them 9-1/2 or 10. It all depends on how high the blood sugar's getting, and as we found out in this study, how long the red blood cells are sticking around.

         Now you understand a little bit about the hemoglobin A1c test, what it actually looks for. What you need to know is red blood cells only live somewhere between 90 and 120 days. They got torn up by the spleen. You make a new one in its place, and they get replaced. That's why it's a 90-day average-ish of blood sugar regulation because after 90 days, presumably, most of those red blood cells have been replaced and you've lost that marker for blood sugar control.

           Knowing that, let's now talk about what they found in this study. What they realized is when thyroid hormone levels are low, when you are in a state where you can be diagnosed as hypothyroid, that slows down the rate at which you're replacing the red blood cells, and when you don't replace the red blood cells as quickly as normal, that 90-day window changes, and so some of those red blood cells that would have been dipped in sugar or sugar-damaged, glycated, glycosylated, live longer in the blood stream, so your hemoglobin A1c numbers are going to start to climb because there's more of it there simply because it's not being pulled out of circulation and replaced.

          When they added thyroid hormone to those patients and put them in a category where they would be considered normal thyroid hormone, then they started turning over their red blood cells appropriately and their A1c numbers went down even their blood sugar never changed. While they were monitoring daily blood sugars, that wasn't an issue, or if it was an issue, it was not as big of an issue as it looked like when they changed the rate at which the red blood cells were turning over. They changed the hemoglobin A1c result even though the blood sugar didn't appreciably or significantly change. That really let them know that hypothyroid patients may look pre-diabetic or diabetic or look like they have poor insulin or sugar control even when they don't, if they don't have enough thyroid hormone.

         Interestingly enough, on the reverse side of that, would a hyperthyroid patient test non-diabetic even when they were. They also looked at that. That didn't seem to be the case. Red blood cell turnover increased when they took a hyperthyroid patient and made them normal. I'm sorry. It decreased when they took a hyperthyroid patient and they made them normal, but it didn't really change the A1c numbers. The A1c numbers were basically stable in that person. It really only looks like it's an issue for hypothyroid patients.

        For patients and for doctors, really, when you see someone with an elevated A1c and you haven't done a full thyroid panel yet, you've only done the TSH or the TSH free thyroxine intake or T3 uptake, when you've done a minimum panel like that, you need to look deeper into thyroid issues to find out if the only reason the A1c was elevated was because thyroid hormone levels were low. Likewise, in a doctor who's following a hypothyroid patient and has them on medication to replace their thyroid hormone, if their A1c is creeping up, but their blood sugar looks normal, you probably haven't gotten their thyroid hormone levels high enough for them to be normal. If you had, that A1c number would not be falsely elevated.

      The two sides of this, one is do a full thyroid panel, TSH, total T4, free T4, total T3, free T3, reverse T3, thyroid peroxidase antibodies and thyroglobulin antibodies. That's a full thyroid panel. That's the way it should be done. If you do that, you will see if there's not enough thyroid hormone even though the TSH may be fine. TSH can be uncoupled with the T4 number pretty regularly, especially if there's an autoimmune issue. A full thyroid panel's important, not necessarily just to diagnose the hypothyroidism. You can technically do that from TSH or T4 because that's what's required, but if you really want to know if the patient has enough thyroid hormone, you need to look further than that. That's what it comes down to.

        Are you looking to technically put them in a box, or do you actually want to know if they have enough thyroid hormone to manage their processes properly? A low T3 or low free T3 can lead to all the symptoms, like hair loss and cold hands and feet and constipation, elevated cholesterol numbers, elevated A1c, even if the TSH and the T4 are pretty normal. If they're not converting that into something useful, you can still have this issue.

        On the flip side of that, when you look at a hemoglobin A1c, also look at their triglycerides, look at their fasting blood sugar, not the best reading. That one's pretty variable. Every day, it can be different. Obviously, several times a day, it can be different. Look at their hemoglobin A1c. Consider maybe pulling a fructosamine because that's a shorter window, but you would have likely the same issue that you have with an A1c and the thyroid hormone. Then look at their fasting insulin level. If this says that they've got insulin resistance, their fasting insulin level is 2-1/2 or 3, something doesn't fit. Go look at the thyroid hormone.

         I know that makes it complicated, but for patients who have low thyroid hormone, the last thing you want to do is look at an A1c and throw them on metformin or something if they really don't need it. That's just going to mess things up even further, and you can be chasing. You put them on metformin, their blood sugar's too low, you take them off, their A1c's too high. It's because it's not high because of the blood sugar.

        I am a huge fan of aggressively treating blood sugar issues, but not if they're not there. I'm also a huge fan of understanding the numbers properly, making sure you don't over-diagnose patients or misdiagnose patients.

      I wanted to bring that article to light. If you are a patient that's hypothyroidism, low thyroid hormone, or you don't think your thyroid hormone dosage is high enough for you, remember the T4 numbers can go anywhere from 6 to 12 and still be in a good, tight, functional range. If you're a 7 and you don't feel right, maybe you need to be a 10. If you're at 7 and your A1c numbers haven't gotten better, maybe you need to be a 10 or 11 or 12 to feel normal for your body. That's a normal range. It doesn't mean that any number within that range is perfect for any patient. That means that if you're in the range, you may need to fiddle with it or you might not, but if you're outside that range, there's likely a problem. Don't misunderstand the range.

        If you don't feel like you're being managed properly, look for some of these signs that maybe your low thyroid hormone is impacting your hemoglobin A1c. Low thyroid hormone can impact cholesterol numbers. How many people are put on statin drugs when they really need thyroid medication? Just be aware that none of these individual tests, none of those organs, glands, hormone levels, they don't live in a vacuum. They're part of a system, part of a body, and they can impact other components of your physiology. Just be aware of that, and don't be afraid to ask your doctor, "Can we run another test? If my A1c is high and I've been paleo for two years, can we look at my thyroid hormone?" If they don't want to do it, find another doctor.

       Functional medicine doctors should have a pretty good understanding of this. Conventional medicine doctors are at somewhat of a disadvantage because their job, because they're paid by the insurance companies, is to reach a diagnosis. They want to see if you fit diagnostic criteria. Their job is not to make you healthy. Their job is not to normalize your physiology. Their job is to diagnose you and then apply whatever approved protocol there is for that diagnosis. If you're looking for a detective to say, "Okay, my A1c is high, but my fasting blood sugar is always fine, why is that the case," you are probably outside the realm of your regular family doctor. You always find a few that just love to roll up their sleeves and dig into that, and that's great, but, by and large, they don't have the time. They're not paid for the time to dig through all that for you, so find a functional medicine doctor and figure out what's going on.

       Anyway, wanted to let you know that's what's in there. That's why we do the annual physical blood work that we do that includes a full thyroid panel, a full blood sugar workup that we talked about. It looks at the cholesterol numbers, liver function, kidney function, vitamin D levels, certain inflammatory markers, the right kind of of magnesium. It looks at all of that. All right. That's the way it ought to be done every year so you know what's really going on and what's just kind of a misinterpretation.

      All right. I know this is going to generate some questions. Type them in below. I'll do my best to answer them as quickly as I can. Tag some friends that you think have thyroid issues and type 2 diabetes kind of issues and let them know about this so that they're aware of it and they can educate their clinician. All right. That's it for today. I hope you guys have a good afternoon. If you don't catch one of my other videos in the next day or two, I hope you have a Merry Christmas, and I will see you guys soon. Have a good afternoon.


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