Where does blood sugar (glucose) come from?

The main source of sugar in your blood comes directly from the foods you eat. Some examples of these types of foods include rice, potatoes, pasta and bread, as well as sugary foods such as cookies, cakes, and pastries. When glucose enters the bloodstream after you eat carbohydrates, it goes through the pancreas. The pancreas secretes insulin when you consume carbohydrates and sends excess glucose to the liver as glycogen. The pancreases also produces glucagon, which actually raises blood sugar when necessary. You need both glycogen and glucagon to keep blood sugar levels balanced.