Eating too much sugar are you? The normal blood sugar levels for humans are around 82 to 110 mg/dl. That's what Wikipedia says anyway. Blood sugar levels tend to rise as soon as you eat and you should not check the levels after a meal. In fact the level can go up to around 140 mg/dl, and this is considered quite normal. There are several ways to test the blood sugar level and this includes urine tests and oral glucose tolerant test. High levels of blood sugar are associated with diabetes eye, heart and kidney disease as well. Hope that helps.