The Blood Sugar System

When you consume carbohydrates through foods, the body converts them to glucose, a simple sugar that serves as a vital energy source. The body does not use this energy all at once. It converts some into stored energy, or storage molecules, called glycogen, and stores it in the liver and the muscles. When the body needs this energy, the glucagon in the liver converts it back to glucose. It enters the bloodstream from the liver. Once in the bloodstream, insulin enables it to enter cells to provide energy for the body’s functions. In the pancreas, islet cells release insulin and glucagon. 

The body’s cells need glucose for energy; insulin attaches to insulin receptors on cells throughout the body, signaling them to open and grant glucose entry. Low levels of insulin constantly circulate throughout the body. A spike in insulin signals to the liver, causing it to absorb glucose and change it to glycogen. When blood sugar levels drop, glucagon instructs the liver to convert the glucagon back to glucose, which causes blood sugar levels to return to normal. 

Blood sugar varies throughout the day and can be affected by food, exercise, sleep, stress, tobacco, and alcohol. 

Blood glucose, or blood sugar, is the main sugar found in the blood of the body. It is the body’s primary source of energy. This comes from the food we eat. Through the digestive system, the body breaks down most of the food we eat into glucose, which is then released into the bloodstream. When the blood glucose goes up, this signals the pancreas to release insulin. Insulin and glucagon help to maintain blood sugar levels. Insulin is a hormone that helps the glucose get into the cells to be then used for energy. Glucagon helps to prevent blood sugar from dropping; it breaks down glycogen into glucose in the liver. Both are essential in balancing and regulating blood sugar levels to maintain homeostasis.