According to the National Institutes of Health (USA), up to half of the American population suffers from some degree of insulin resistance (total diabetic plus prediabetic). Almost forty percent of Americans are classified as prediabetic. These statistics indicate that insulin resistance is at epidemic levels in the United States and, since most other Western cultures tend to follow US trends, it is a safe bet that similar levels of insulin dysfunction can be found amongst most of Europe and any other nation that has adopted a similar lifestyle.
So what is insulin resistance anyway?
Let’s start with insulin by itself.
Insulin, as discussed previously, is a hormone secreted by the pancreas in response to elevated levels of sugar in the blood. It lowers blood sugar by forcing excesses into the cells. The most common analogy used is that of a lock and key. If you think of your cells as a house, insulin is essentially the key to the front door. It opens the door to your cells and forces the excess blood glucose in for use or storage.
In the keto community we frequently talk about insulin as if it were an evil, but the reality is it is not a bad thing at all. It is simply a natural part of the body’s metabolism, a mechanism by which the body breaks down, uses, or stores energy. The problem with insulin is that the very functions that make it a useful tool of the body can also, in excess, harm the body.
Having too much sugar in your bloodstream is highly toxic. This is why the body releases insulin in the first place. It gets rid of the excess in your blood stream. But over time excess glucose INSIDE your cells (where it is stored by insulin) is also toxic and can cause serious damage to your organs.
Excess glucose inside your cells causes something called oxidative stress, which damages your body’s ability to detoxify itself and also damages all parts of the cell, from proteins to lipids, even down to the DNA. Oxidative stress also messes up your cell’s ability to perform cellular signaling, which is the cell’s ability to process and respond to its environment, as well as how it communicates with the rest of the body. When you’re storing excess glucose in your cells, you’re inhibiting your body’s natural detox functions and impairing its ability to react and communicate.
Under normal conditions small amount of oxidative stress can be good, as it can signal to your body the presence of pathogens that need to be taken care of by the immune system. In other words, it’s part of the body’s natural defense mechanism. Constant and persistent oxidative stress, on the other hand, is bad, as it has the body’s immune system constantly stirred up into attack mode (which is what we refer to as chronic inflammation). Oxidative stress is believed to be an underlying factor in the whole gamut of diseases and medical conditions.
Another part of your body’s natural defenses is the ability to develop a resistance to substances that are causing harm. In the case of insulin, when we are constantly feeding our body a lot of excess glucose and insulin is then constantly shoving large excesses of glucose into our cells, those cells react in self-defense by becoming resistant to the insulin. Going back to our house analogy, when resistance develops the cell, in essence, changes the size of the key to its front door, so now it requires a much bigger key to open. Therefore, more insulin must be produced in order to open our cells for storage of excess glucose.
A flow chart of this process would look like this:
Excess blood glucose—> Insulin secretion—> Cells open and absorb excess glucose—-> Excess glucose causes oxidative stress, inflammation, and cell damage—> Cell develops insulin resistance in response to the damage caused by the excess glucose—> Normal amounts of insulin are no longer sufficient to open the cell—> Excess blood glucose
At the end of all that you have excess blood glucose, yet again.
Here’s the thing: insulin resistance on the surface is not a bad thing. It’s a natural part of our body’s defense mechanism. It’s there to keep cell damage to a minimum. But what happens when we continue to feed our bodies excess glucose? Once the cells begin to suffer damage from excess glucose and oxidative stress, insulin resistance develops into an even greater resistance and then we have a reinforcing circle of glucose, insulin, cell damage, resistance, then back to excess glucose. The initial development of insulin resistance sends your cells into a cycle of increasing resistance.
The key to reducing insulin resistance, or preventing it altogether, is to regulate intake of substances that are going to be broken down and converted into blood glucose. In other words, we have to limit primarily carbohydrates. This is a BIG part of the Why behind Ketogenic living. When we limit carbohydrate intake we can, to a large degree, control insulin release. For people who already have some measure of insulin resistance (and if you are obese the likelihood that you have IR is high indeed) this is essential in stopping the damage to our bodies and reversing the cycle of sugar intolerance.
Another aspect to why insulin resistance is so detrimental is because it promotes fat storage, which I will discuss next week in my final entry into this series on metabolism.
Stay tuned, and stay keto.