Actually blood sugar is the glucose concentration that cirulate in the bloodstream.
Glucose has a signaling function for metabolism – the presence of sugar in the blood. That´s why blood glucose is called (even in a very specialized context) ‘blood sugar’. Glucose is transported through the bloodstream from the digestive tract to individual body cells. It is the main source of energy for the body.
If body is unable to regulate blood sugar levels, it is called hypoglycemia – low blood sugar or hyperglycemia – high blood sugar.
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