People who are insulin resistant also have high blood pressure, and insulin resistance is directly caused by a high sugar, high grain diet. As your insulin level increases, so does your blood pressure. Insulin stores magnesium, but if your insulin receptors are blunted and cells grow resistant to insulin, you can’t store magnesium so it passes out of your body through urination. Magnesium in your cells relax muscles. If your magnesium level is too low, your blood vessels will constrict.