Dr. Tabatha Barber explains that lab "normal" ranges capture 95% of tested people, including sick ones, so being normal doesn't mean healthy. Reference ranges shift as populations get sicker: glucose ranges rise as more people develop high blood sugar, making illness look normal.
We have done a real disservice to our country, really, in telling them that they are normal because they interpret that and we've made them think that means healthy. So normal ranges doesn't mean healthy ranges. The normal range that you're given on that paper is actually just telling you this is where 95% of people who were checked for the lab, that is where they fall, healthy or not. So it's just the combination of everybody. And so that's where we, when we practice here, we want to compare you just to those healthy people. We don't want to compare you to the sick people. And that's what the majority of those reference ranges or those normal ranges are telling you is where the majority of the population falls. I just had these back recently on a couple labs. And because this is a range that's based on the population, these change. Okay. So you would think that if this was normal, or if this was healthy, the range would always be the same, but that is not what happens. And we'll see that on the lab printouts where it will say, "Note, reference interval has changed." And so I have seen the normal blood sugar range change to go higher, not because it's healthy, but because more and more people have higher blood sugars. And so now we have a new normal. So it just makes us think as a population and as a country that, "Oh, we're still healthy," but really we're just getting sicker and the ranges are just changing to make us look healthy.
