The amount of glucose contained in the blood is called Blood Sugar. Glucose which is run through the bloodstream is the primary source of energy for the body's cells.
Blood sugar level is tightly regulated in the human body. Normally the blood glucose level is mtained between about 70 to 100 mg/dL. The total measurement of glucose in the circulated blood is therefore about 3.3 to 7 g which is based on the assumption that an ordinary adult blood volume is of 5 litres). Glucose levels rise after means and are usually lowest in the morning before the first meal / breakfast of the day.
A blood glucose test measures the amount of a type of sugar called glucose in our blood. Glucose comes from carbohydrate foods. It is the main source of energy used by the body. Insulin is a hormone which helps our body's cells use the glucose. Insulin is produced in the pancreas and released into the blood when the amount of glucose in the blood rises.
Normally, our blood glucose levels increase slightly after we eat. This increase causes our pancreas to release insulin so that our blood glucose levels donot get too high. Blood glucose levels that remain high over time can damage our eyes, kidneys, nerves and blood vessels.
There are several types of blood glucose tests that are used e.g. (1) Fasting blood sugar, which measures blood glucose after we have not eaten for atleast 8 hours. This is often the first test done to check for diabetes (2) 2-hour postprandial blood sugar, which measures blood glucose exactly 2 hours after we eat a meal (3) Random blood sugar measures blood glucose regardless of when we last ate. Several random measurements may be taken throughout the day. Random testing is useful because glucose levels in healthy people donot vary widely throughout the day. Blood glucose levels that vary widely may indicate a problem. This test is also called a casual glucose test.
Oral glucose tolerance test is used to diagnose prediabetes and diabetes. An oral glucose toleranfe test is a series of blood glucose measurements taken after we drink a sweet liquid that contains glucose. This test is commonly used to diagnose diabetes that occurs during pregnancy.