Using high-resolution microscopy, researchers have shown how insulin prompts fat cells to take in glucose in a rat model. By studying the surface of healthy, live fat cells in rats, researchers were able to understand the process by which cells take in glucose. Next, they plan to observe the fat cells of people with varying degrees of insulin sensitivity, including insulin resistance-considered a precursor to type 2 diabetes. These observations may help identify the interval when someone becomes at risk for developing diabetes.