7. Lightheaded Feeling
Some more common symptoms of high blood sugar are if you are unexplainably light headed. If you ever feel this way and you are not starving, you might want to be checked out. Very high blood sugar levels tend to have the symptom of lightheadedness, which can cause brief blackouts, loss of consciousness, or even worse. If you experience this symptom, it is important to be assessed by a doctor or healthcare physician immediately, as you might have a serious problem.