In the last post we looked at some concerns from internet blogger Jenny Ruhl in an article she wrote about high blood sugar and damage. She goes go on in the article to express further concerns about blood sugar over this range and beta cell loss, and that's a topic that should interest us as well, so in this post I want to talk about that a little more.
I want to provide you with an excellent article in Diabetes Care about beta cell loss and the progression of type 2 diabetes in general, and it's not a very difficult read at all as far as scientific articles go, and is well worth looking at, especially since I'm only going to be covering a few points that the article makes.
I actually want to do at least one more post or article on this site covering this, but for now, we'll just talk about beta cell loss and the progression of diabetes.
I want to point out that the blood sugar she is concerned about in her article is in the prediabetic range, not the diabetic range, although she believes that blood sugar in the prediabetic range is dangerous, in spite of the science we have not supporting this view, and the real risk with prediabetic numbers is seeing them climb to the threshold of diabetes and beyond, and it's the beyond part that is where the real concern lies.
There isn't a significant difference between the risk of complications with blood sugar below diabetic levels compared with normal levels, which I spoke about last time, so if you haven't read that post yet and you want to read more about this part of it then you're welcome to do so.
We do know that prediabetics experience beta cell loss though, and in fact, the beta cell loss starts to occur several years before blood sugar even starts to rise at all, and this loss of beta cell function plays a role in the pathogenesis of diabetes, although this does tend to be overstated, as it's not that we are dealing with normal levels of glucose load with even prediabetes, in other words there's more glucose to deal with and that plays a big role in diabetic hyperglycemia.
So in other words it's not that our beta cells are failing to the point where we cannot make enough insulin anymore, it's that our insulin requirements keep going up and up and we end up surpassing our capacity, which is actually a good thing since high insulin levels are harmful and we already see harmful levels even though we're supposed to have a "relative" insulin deficiency.
However it's true that our beta cell mass does decline along the way toward diabetes, even though this is not central to the problem and not even relevant at this stage. Over time though, over many years of uncontrolled blood sugar, our beta cells can get to the point where they can no longer produce normal levels of insulin, from beta cell loss over a very long period of blood sugar dysregulation, so this stuff does matter as we don't want to get to that point because this is where we become insulin dependent.
Since we do get this beta cell loss long before our blood sugar even goes up, that should tell you that there is more going on than high blood sugar, and there certainly is. The primary mechanism that kills beta cells is actually poisoning by fat, and this is primarily caused by high insulin levels, and that's something we definitely need to be wary of.
Mild to moderate hyperglycemia, and prediabetes is of the mild variety by the way, does cause some beta cell dysfunction, and how it does it is reducing our insulin storage, because insulin is being released all of the time to combat the higher blood sugar and then when we eat a meal, our phase 1 insulin response, the release of the insulin that we store for such occasions, is either depleted or absent.
Blood sugar that is very high may cause more than trivial beta cell death in itself, although we're talking very high blood sugar here, levels that are way higher than 140 by the way.
Now it is actually normal for beta cells to die even without high blood sugar, so showing that beta cells die at 140 or whatever is trivial and meaningless. So it's only when this beta cell death results in a significant loss that this is meaningful, and also a significant net loss as well, meaning a lot more die than are replaced, and we do grow new beta cells by the way.
There are a lot of prediabetics that go over 140 as well by the way that never get diabetes, and since they have prediabetic blood sugar, we know it can't just be the blood sugar that does it, and we know for sure that it doesn't, and it's not even the blood sugar that does us in at this point.
We can't say that someone loses beta cells at 140 or 150 or whatever, therefore the blood sugar did it, this is another mistake Jenny makes. There isn't even a good reason to think that the blood sugar itself had anything to do with it at this level, and given the fact that we see various degrees of progression of diabetes at these stages, often without any at all, it's not the blood sugar.
Rather, it's the high levels of insulin resulting in higher levels of free fatty acids in the blood, that's the primary mechanism anyway, although inflammation plays a significant role as well, and high insulin both causes elevated free fatty acids and is also inflammatory.
So when we look at blood sugar here we're actually looking at the wrong thing, we should be looking at insulin itself, and hyperinsulinemia is where this process all starts, it's what we get first, and the beta cells start dying off way back then.
Beta cell health plays a fairly minor role in diabetes by the way until in the late stages, where we do we see insulin secretion actually go low, if it's too high we surely can't say that we are deficient in this, and the problem lies elsewhere. It indeed does, as our problem from the very beginning until very late in the progression of diabetes is the opposite, not a deficiency of insulin, but rather a pathological excess.