Blood glucose
Need to know
- The sugar in the blood is called glucose.
- There should only be 4 to 5 grammes (about 1 teaspoon) of glucose in the blood.
- Glucose in the blood comes from food and it can be made by the liver.
In-depth
The proper name for blood sugar is blood glucose.
Glucose is one type of sugar that is found in nature.
Plants make glucose. They may then join it into long chains. These long chains of glucose are called starch. Glucose and starch are known as carbohydrates. When we eat foods containing these carbohydrates the gut will break the food down into glucose molecules. The glucose then enters the bloodstream, resulting in an increase in the blood glucose level.
Glucose, in addition to coming from food, can also come from the liver. Our liver is able to make and store glucose. If we haven't eaten any sugar or starch for a few hours the liver will release stored glucose into the blood. This means it is possible for humans to live without having to eat any sugar or starch.
There should only be about 4 to 5 grammes (1 teaspoon) of glucose in all the five litres (8 pints) of blood in the body. Too little or too much glucose in the blood can be extremely harmful. Potentially fatal. To make sure blood glucose does not go too high the pancreas releases a hormone called insulin.