Blood sugar refers to the amount of sugar--or glucose--in your blood. The hormone insulin helps the body process and use glucose. Normally, blood sugar increases after eating, and the pancreas releases insulin to regulate glucose levels. In people with diabetes (high blood sugar) or hypoglycemia (low blood sugar), the body is not able to regulate blood sugar on its own, resulting in sometimes very dangerous reactions.
High Blood Sugar
High blood sugar occurs when there is not enough insulin produced, or when the body cannot properly process insulin. Blood sugar that remains high for a long time can cause serious damage to the eyes, kidneys and nerves. Some signs of high blood sugar include high blood glucose levels in a blood or urine test, frequent urination and an increase in thirst.
Low Blood Sugar
Low blood sugar can be caused by stress, hunger and insulin reactions. If you have been diagnosed with hypoglycemia or with diabetes, it is important to recognize the symptoms of hypoglycemia and to know how to treat this condition. Symptoms include shakiness and dizziness, sweating, severe feelings of hunger, sudden moodiness, lack of concentration and clumsiness.
Normal Levels of Blood Sugar
There are several types of blood glucose tests, which include fasting blood sugar, postprandial blood sugar and random blood sugar testing. Fasting blood sugar tests measure glucose levels after 8 hours without food or drink and should result in a normal range of 70 to 99 milligrams glucose per deciliter of blood; postprandial blood sugar tests measure glucose levels within two hours after eating and should result in a range of 70 to 145 mg/dL; random blood sugar tests are taken at intervals throughout the day and should result in glucose levels of 70 to125 mg/dL. Blood sugar levels higher or lower than these ranges are not considered normal and should be monitored closely. Danger zones include fasting blood sugar above 126 mg/dl or below 50 mg/dl.