If a doctor is concerned that a patient either has diabetes or is at risk from diabetes, they might suggest an A1C test to be performed. And what I want to do in this video is, one, just explore what A1C even means, and also how that actually relates to diabetes, or the main side effect of diabetes, which is having high blood sugar, or hyperglycemia. So to do that, let's think about Let's think about red blood cells.
And I know what you're thinking. What does this have to do with diabetes? And we'll get there in a little bit. So red blood cells are the main oxygen carriers in our blood.
They kind of look like these lozenges. And inside of red blood cells, you have hundreds of millions of hemoglobin molecules, or hemoglobin proteins. Let me draw some hemoglobin proteins. You actually have the number I found is 200 to 300 million per.
per red blood cell. And then we have tens of trillions of red blood cells. So we have a lot of hemoglobin in us.
And hemoglobin is what makes red blood cells red. When hemoglobin is bound to oxygen, it has a red color. So this right here, each of those are a hemoglobin protein.
Now, it turns out that hemoglobin, let me draw a bigger version of it. If it has some glucose around, so let me draw some glucose floating around near the hemoglobin. If it has some glucose around, there's some chance, it's not a high probability, but there's some chance if the hemoglobin and the glucose bump into each other in just the right way, that they'll bind to each other. And so you'll have this situation where you have glucose bound to the hemoglobin.
Now, this hemoglobin with a glucose bound to it is called glycated hemoglobin. Glycated hemoglobin. I wrote glycated in green because I'm using green for the glucose. So glycated hemoglobin. And another name for glycated hemoglobin, or a hemoglobin that has some glucose bound to it, is hemoglobin A1C.
And now I can imagine things are starting to click in your brain. When you are measuring your A1C levels, that's a test of the percentage of your hemoglobin that is hemoglobin A1C. So you take a blood test, they're measuring relative to the total amount of hemoglobin there, what percentage of that is hemoglobin A1C?
And a normal range of that. So if you just have normal blood sugar over a reasonable amount of time, you're going to have a hemoglobin A1C level in kind of the 4 to 6% range. And people are still kind of trying to tighten up these ranges and it doesn't completely correlate tightly with blood sugar.
It does correlate, but people with the same blood sugar can still have fairly different A1C levels. But 4 to 6% is considered normal. And if you have higher Higher than 7% or 8%, so greater than 7% to 8%. So if you had an A1C level of 9% or 10%, that's high.
And so you can imagine this is kind of a proxy for how much glucose you have in your bloodstream. Because the more glucose that you have in your bloodstream, the higher the probability that that glucose is going to react with the actual hemoglobin. So you're going to have a higher percentage of hemoglobin A1C.
And the other reason why this is useful, and it's kind of, well, I guess you could see on the first pass, it's useful because it's not one of these snapshot tests. Everything we've talked about so far with respect to diabetes is taking your blood sugar at any one point in time. And we know that your blood sugar changes throughout the day. It changes depending on how active you are. It changes depending on what you might have just eaten.
So when you do blood sugar, you're just getting a sample. You don't know what the blood sugar is throughout the day, unless you just kept sampling it, which could get pretty annoying. Keep.
keep pricking your needle. With A1c, this starts to become a measure of how much glucose you have in your blood over a longer period of time. And in general, it's kind of used as a measure for the last few months because the red blood cells and the hemoglobin in them, they have a lifespan of about 120 days.
120 day lifespan. Now that obviously doesn't mean that all of your hemoglobin gets produced on one day and then all dies 120 days later. You have some red blood cells in hemoglobin that might be a few seconds old, and then you have some that might be approaching 120 days old. So on average, they're going to be about 60 days old or about two months old.
So when you're measuring this percentage, you're definitely not getting the percentage of anything older than 120 days, and on average, you're seeing things that are from about two months old. So the higher this percentage, this is saying, wow, my average hemoglobin molecule in my body is only maybe 60 days old at this point, and already 7% to 8% of them have already been glycated, which is an indicator that I probably have more blood sugar than a normal person. In a normal situation, only 4% to 6% of my hemoglobin would get glycated. So hopefully that explains what A1C is.
But I do want to say, and I said at the beginning of the video, I'm not a doctor, and even amongst doctors, the A1C is a very important factor. test or the A1C measurement, there's some debate about how useful it is, what it's measuring or how far back it actually is a good view at your glucose levels. And also, as I mentioned, two people with the exact same blood sugars could have different A1C levels depending on other things, how old they are or whether they have some other type of medical condition.