In clinical practice, two methods of blood glucose monitoring are generally used. One method is in hospitals, where medical staff measure blood glucose by drawing blood from a vein, and the blood glucose measured is plasma glucose. The other method is to cut the finger with a glucose meter, and the blood glucose measured is whole blood glucose. In fact, venous blood glucose is about 15% higher than fingertip blood glucose because fingertip blood glucose is whole blood, which contains a portion of red blood cells, and the red blood cells absorb about 15% of the glucose level to metabolize as energy, so venous blood glucose is higher than fingertip blood glucose. Patients who need to diagnose diabetes should go to the hospital to have their venous blood glucose drawn. If a diabetic is being treated at home to monitor his or her blood glucose, it is perfectly fine to use fingertip blood glucose.