We’ve now looked at the two main characteristics used to describe what goes on with type 2 diabetes, and I’ve decided to leave the not enough insulin one in there even though this is generally not the case with us.
We’ve also spoken about how often we have too much insulin and when I say too much I mean higher and usually much higher levels than normal physiological levels of this hormone. When we measure hormone levels, we always use normal physiological levels as the baseline, and there’s no question that the majority of type 2 diabetics exceed these levels.
Insulin resistance makes the grade as well, and we definitely all have that, and usually quite a bit of it. It isn’t just a matter of just saying we have insulin resistance though, this is pretty complex and there are a number of things involved in this, as you will see as we progress, but at the very least if we are going to say it’s not enough insulin and/or insulin resistance, and if someone makes plenty of insulin, therefore the first condition doesn’t apply and the second one clearly does, so you would think we’d be paying a lot of attention to trying to reduce insulin resistance, but the truth is, we tend to want to do the opposite.
So I’ll get back to that but I want to introduce you to another component here, one that we know a lot about but it rarely ever comes up in discussions about diabetes, and that’s the hormone glucagon.
Insulin is secreted by the beta cells of the pancreas of course, and glucagon happens to be secreted by the alpha cells of the pancreas.
So what does glucagon do? Well it’s the opposite of insulin, insulin seeks to put our blood sugar down, while glucagon seeks to put it up. If not for glucagon we would die of low blood sugar when we go without eating, as the body requires another source of blood glucose besides what you eat, and glucagon thereby serves an essential function in maintaining life, by basically instructing the liver to pump glucose into our blood to keep our blood sugar from going too low.
In order for glucagon to perform this role though, it has to be boss, meaning that it needs to work regardless of whatever is going on in the body. In fact, type 1’s use glucagon pens to treat severe, life threatening low blood sugar, and the glucagon comes to the rescue no matter how much insulin or how little glucose you have in your blood. This doesn’t mess around with injested glucose at all, it raises blood sugar much more direct and quickly than that.
The normal pancreas will only secrete appropriate amounts of insulin under normal circumstances, and will also only secrete appropriate amounts of glucagon as well. Those are under normal circumstances though, and type 2 diabetes is not a normal circumstance, especially when it comes to the workings of the pancreas.
So our insulin levels are higher than normal and our glucagon levels are as well, and high glucagon levels will raise blood sugar as sure as the sun rises. It has to because otherwise we would have to eat at regular intervals or die, but we can live for many months without eating anything, and glucagon is to thank for this.
So these two hormones work together and when glucagon senses little insulin it thinks well this person hasn’t eaten for a while, and it’s time to spring into action. When the alpha cells aren’t able to properly detect insulin though, meaning insulin might be telling them to be quiet but they aren’t getting the message properly, then glucagon and insulin can both be high at the same time.
So that’s our introduction to glucagon and you can see that this is certainly worthy of our things that go wrong in type 2 diabetes, it’s the big one actually, but hardly anyone pays any attention to it, but we really need to.