Cut back on sweets, refined grains, and animal fats, and have lots of vegetables, fruits, and whole grains. That kind of eating plan will help you get to and stay at a healthy weight. It also helps your cells use insulin better. The DASH diet, for people with high blood pressure, is a good example. It includes cutting down on salt, too. It can lower insulin resistance, especially if you slim down and become more active while you're at it. Studies have also shown a link between low vitamin D and your body not using insulin well.