It is used to determine the level of glucose in the blood. It can be used to detect diabetes (diabetes mellitus) and to control the blood sugar level of a diabetic.
The most important hormones in regulating blood sugar are insulin, which lowers blood sugar, and glucagon, which raises blood sugar. Both are produced by the pancreas. Blood sugar levels can be measured at any time of the day, but if blood is not drawn on an empty stomach, the result will be affected by the consumed food, drink, and physical activity.
High blood sugar (hyperglycaemia) may be a sign of diabetes, so further tests may be needed. However, elevated blood sugar levels can also be a symptom of many diseases, including hyperthyroidism, inflammation of the pancreas, but it can also accompany other hormonal disorders, as many drugs can cause hyperglycaemia.
Low blood sugar (hypoglycaemia) may indicate hypothyroidism or other hormonal disorders, may be a symptom of an insulin-producing tumour, but is most often the result of an insulin overdose.