HbA1c

Hello, readers!  Today we're going to talk about how people are actually diagnosed with type 2 diabetes.

As I mentioned in my last post, one of the defining factors for being diagnosed with diabetes is not insulin resistance but a number called HbA1c (which stands for "glycated hemoglobin").  If it's above 6.5, you can be medically diagnosed with type 2 diabetes--if it's only a little bit lower, you are what we can call "prediabetic," or, on your way to developing diabetes if things continue the way they are going now.  Either that, or you're diagnosed with "metabolic syndrome," which is just as vague as it sounds.

There's something wrong with you metabolically, but we don't know what to classify it as!

Metabolic syndrome includes symptoms like high blood pressure, obesity, LDL problems, and, shockingly, insulin resistance.  That's...a pretty wide range of symptoms, there.

Anyway, returning to HbA1c.  If you have diabetes, your blood sugar is perpetually high because your body can't produce enough insulin to lower it again because you're insulin resistant.  All this glucose floats around in your bloodstream for a while, just taking up space.

Like this rebellious teenager.

The thing about glucose is that it's really, really sticky.  This causes problems in a bunch of the parts of the body, mostly in nervous tissue, as glucose sticks to nerves and makes them slow down a lot, which can cause blindness and other health problems.  This also makes wounds harder to treat in the hospital, because all the glucose hanging out in the tissue slows down the healing process tremendously.

One of the things glucose sticks to is the hemoglobin in red blood cells--the longer a person is hyperglycemic, the more glucose sticks itself to the hemoglobin molecules.  And, since glucose is so sticky, it stays that way for the duration of the life of the red blood cell.  Since red blood cells last for about 2 weeks, this provides a long-term test for finding the amount of glucose stuck to red blood cells, an indicator for type 2 diabetes.

The shark is the hemoglobin, and the remoras are glucose molecules.

As long as HbA1c is above 6.5, that is.  If you're stuck at 6.4, you can't be diagnosed and/or treated for diabetes, so you can't be given insulin to offset the resistance you've built up.

The thing is though, if you treat insulin resistance using, say, a lifestyle change that dramatically reduces the daily intake of glucose molecules, you'll have less glucose floating around in your bloodstream, and thus less to attach to hemoglobin molecules in red blood cells, and thus a lower HbA1c.  Just putting that out there.