How come patients with diabetes mellitus type 2 are insulin resistant?

Insulin resistance: In patients with type 2 dm , Insulin resistance is one of the factors in addition to decreasing Insulin production. There are what are called Insulin receptors in the cells that Insulin attaches itself for its action. These receptors are down regulated or less in number. Sometimes, increasing the dose of Insulin may not work always because of this reason.

Partially Understood: Type ii dm typically develops slowly over decades without symptoms. Insulin resistance 1st, pancreas ↑es insulin+amylin output, up to 5x’s healthy. Sugar/carb intake ↑es Insulin output & drives storage as fat; fat cells binds Insulin more than muscle, thus vicious cycle. Low muscle mass & use ↓es muscle use of glucose, so more storage into fat. Fat secretes resistin which inhibits Insulin action.