Insulin regulates blood sugar levels. It tells cells to start pulling glucose out of the bloodstream for storage as glycogen or as fat. Insulin levels are controlled by the pancreatic system, which helps regulate blood sugar levels.

Insulin resistance is when cells are not as responsive to insulin, so blood sugar levels rise to unhealthy levels. Temporary high blood sugar isn’t a problem, but if it’s sustained, it can lead to significant health problems, like kidney damage/failure and ketoacidosis (which can then lead to heart attacks), among other, more minor symptoms.

Hm. Is it known how insulin resistance happens? For example does insulin resistance start first from a cause on it's own and then the resistance causes diseases like PCOS/Diabetes or do the diseases cause insulin resistance? Or neither/some mix of the two??

Insulin resistance is a precursor to diabetes. Insulin rises and falls in response to blood glucose levels. Depending on what and how you eat, those blood glucose levels may not fall enough, and you can eventually put yourself in a situation where the amount of insulin needed to get your body to use blood glucose gets so high that your pancreas can no longer produce enough.

Hm so insulin resistance is caused by diet. Is insulin resistance reversible with diet change then or is it kind of one of those things where the damage is done but diet change can mitigate it to a certain point? I've seen where it's been said diabetes can be reversed depending on the type of diabetes (not the type where you're born with it, only the type where you acquire the disease) and now I'm assuming since the two are linked that if you reverse insulin resistance that equally reverses diabetes? Not sure if that's an accurate way to look at that

Insulin is a key that open the cells doors for sugar to enter and be used as fuel.

In insulin resistance the keyhole is blocked.

The body thinks there is a lack of keys because cells are screaming for fuel and it knows there is fuel. So it makes more insulin. This works for a time, basically forcing the locks.

But if not controlled even the excess insulin is not enough anymore.

The body is flooded with sugar it can't use and it ends up with diabetes.

As to why the keyholes get blocked... why does anything else go wrong in our bodies? Sometimes it's genetics, sometimes it's environmental, sometimes it's a combination of factors (like the change in hormones and the weight gain from pcos).

Interesting. So we know the sugar being unable to be processed and building up in our body leads to diabetes, and the reason it can't be processed is due to the insulin resistance.

You mentioned that the body will try to provide additional insulin to attempt to "force the locks" in this example. Is there any impact from the excess insulin in our body? Or does it not build up the same way because it gets used (unfortunately unsuccessfully) when trying to process the sugar?

Insulin is an hormone. Any anormal hormonal level is bound to have consequences. Here it's called hyperinsulinemia if you want to read about it.

https://en.m.wikipedia.org/wiki/Hyperinsulinemia

....this is going to sound really stupid but never once have I ever actually realized wtf insulin is and that it, in fact, is a hormone.....welp my mind exploded just now.