Food is fuel for our every cell of our body. When we eat food our digestive system breaks down our food into one of three chemical groups, glucose, amino acids or fats.
Glucose is released into our blood stream so it can be delivered to each of our cells. Once our blood sugar level begins to in the bloodstream sensors in our pancreas release a hormone called insulin. Insulin then goes to each of our cells and attaches to an insulin receptor in our cells that allows the glucose to leave the bloodstream and enter the cells. Once glucose enters the cell it is used as energy for each of our cells. As more of our cells take in the glucose from our bloodstream the level of glucose in the bloodstream begins to decrease. As the glucose level in the bloodstream decreases we start to feel a sense of hunger and want to eat to start the process over again. The pancreas sensing that our blood sugar level is dropping will release another hormone called glucagon to cause the liver and the muscles to release glucose that has been stored in those organs to bring our blood sugar back up again. This is the simple process of how we use food as fuel.
When a patient is diagnosed with Type 1 diabetes what has happened is that the pancreas is not functioning correctly and is not releasing any or enough insulin to open up the cells so that glucose can get into the cell to be used as fuel. When there is not enough insulin then the glucose remains in the bloodstream and causes the blood glucose levels to become high. There is so much glucose in the blood that it also gets excreted through the urine and this is how blood and urine test can both be used to diagnose diabetes.
When a patient has Type 2 diabetes, the process is a little different. In this case after a meal the glucose goes into the bloodstream and insulin is released from the pancreas but the cells become resistance to the insulin and so the insulin is not attaching to the receptors as well as it should. The pancreas is still producing and releasing more and more insulin until the cells finally start to respond by helping the glucose get into the cells.