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Most of the food we eat is turned into glucose (sugar) that our body uses to obtain energy. Insulin is a hormone needed to help glucose enter the body's cells and to order them to convert this sugar and other food into energy.
When you have diabetes, your body either does not produce enough insulin, cannot use its own insulin as well as it should, or both. This causes too much sugar to accumulate in blood.
Taking a blood sample with a meter that verifies glucose levels can help you make decisions about both food and physical activity, as well as about medications which help control diabetes.
