Muffler (silver) and exhaust pipe on a Ducati 695 motorcycle. A muffler (silencer in English) is a device for reducing the amount of noise emitted by the exhaust of an internal combustion engine.
Quick Answer. Normal blood sugar levels should be  less than 100 mg/dL when fasting and less than 140 mg/dL two hours after eating, according to WebMD. People without diabetes tend to have blood sugar levels of around 60 to 90 mg/dL before eating.
Normal blood sugar should range from 80 to 100 mg/dL. Low blood sugar occurs when your blood glucose drops below 70 mg/dL. The hormone insulin helps maintain your blood glucose. After you eat, your blood sugar increases and your body secretes insulin to bring your blood sugar back to normal.