Because the body can't produce insulin it has to be introduced artificially, by injections.
Children normally need to inject insulin between and two and four times a day.
Most people with diabetes need to check their blood glucose levels throughout the day.
If the levels are too low, this can lead to hypoglycaemia (hypo) which should be treated immediately with a fast acting carbohydrate such as an energy drink. This should be followed with a sandwich, fruit, biscuits or your next meal if it is due to prevent another hypo.
Symptoms can include feeling hungry, shaky, sweating, tingling lips and feeling confused.
If blood glucose levels are too high, this can lead to a dangerous condition called diabetic ketacidosis, which if untreated can lead to vomiting, drowsiness and eventually a coma. Medical attention should be sought immediately.