Go to page content

Low blood sugar in diabetes

Low blood sugar (hypoglycaemia) means that the blood glucose level or blood sugar is below 4 millimoles per litre

In type 1 diabetes, low blood sugar levels that you can treat yourself occur more or less on a daily basis. In type 2 diabetes treated with insulin, they are normally less common. In normal use, standard diabetes tablets do not cause your blood sugar to drop too low.

For a person with diabetes, low blood sugar is usually associated with too much insulin effect in relation to eating or exercise. Low blood sugar is called hypoglycaemia, and in everyday language, "hypo". Glycaemia means "glucose in the blood" and the prefix hypo means low or deficient.

Hypoglycaemia is divided into:

Mild hypoglycaemia

Mild hypoglycemia refers to situations where blood sugar levels are between 3.0-3.9 mmol/l. Although symptoms of low blood sugar can be quite intense or milder at this level depending on the individual, hypoglycemia does not yet affect the person's ability to function, and they can manage the situation themselves by eating fast-acting carbohydrates or reducing their dose of rapid-acting insulin before a meal, as appropriate.

Significant hypoglycaemia

Significant hypoglycemia refers to situations when self-measurement or glucose sensor readings (for at least 15 minutes) or laboratory test show a blood sugar level of < 3.0 mmol/l. Symptoms of hypoglycemia are clearly noticeable, but they do not involve serious impairment of functioning, and the person is able to still correct their blood sugar levels themselves.

Severe hypoglycaemia

Severe hypoglyvcaemia does not have a specific blood sugar level limit. Your ability to function and cognitive skills are impaired, and you need the help of another person to correct hypoglycaemia.

Aim is a minimal amount of hypoglycaemias

Regardless of whether the blood sugar is above or below three, hypoglycemia is always an unpleasant experience for people with diabetes, and frequent occurrences of low blood sugar can strain both the body and the capacity to cope with diabetes. Particularly significant and severe hypoglycemias may also increase fears related to low blood sugar, which can further complicate the ability to persevere with and implement treatment. Therefore, living a life free of too low blood sugar leves is one of the central goals of diabetes treatment.

Updated 30.9.2023