A fasting blood sugar test measures the level of glucose in your blood after you have not eaten for at least 8 hours. This test is commonly used to diagnose conditions like diabetes or prediabetes. It helps healthcare providers understand how well your body manages sugar levels when not influenced by recent food intake. During the test, a healthcare professional will take a blood sample, usually from your arm. The results indicate whether your blood sugar levels are normal, elevated, or indicative of diabetes. It is a simple and effective way to assess your metabolic health.