In the pre-meal and post-meal test, you check your blood sugar before eating and roughly two hours after starting the meal. If the pancreas secretes insulin normally, eating raises the blood sugar level by a maximum of 2–3 mmol/l, depending on the quality and quantity of food.
The pre-meal and post-meal tests show the effect different food choices, the quantity of food as well as treatment have on blood sugar. The pre-meal and post-meal tests also help establish the correct rapid insulin-to-carbohydrate ratio at different times of the day.
If your blood sugar repeatedly remains too high after a specific meal, you should examine your eating habits, possible need for changes or consider enhancing your treatment. If you use mealtime insulin, you should consider the dose and the time when you take the insulin.