Everyone with type 1 diabetes takes insulin with meals to compensate for the carbohydrate total of the meal. You may take an injection, or you may initiate a bolus from your insulin pump. Some people with type 2 may take insulin injections related to food also, although it’s much more common that type 2s take long acting insulin which is unrelated to meals.
If you take short or fast acting insulin before meals, there are a few things that need consideration.
You need to know your current blood glucose level.
You need to estimate how many grams of carbohydrate you intend to eat.
You need to know your insulin to carb ratio — one unit of insulin will account for how many grams of carbohydrate?
You need to know how to correct for your current blood glucose — less insulin if your blood glucose level is on the low side, and more insulin if blood glucose is elevated.
That is a bunch of need-to-knows. If you’re using an insulin pump, your insulin to carb ratio and correction factor should be programmed into the control.
Your insulin to carb ratio or your correction factor are unique to you. Your doctor will start you with dosages based upon your size and age, and together you can fine tune based on trial and error. Eventually, your dosages for eating or correcting blood glucose may be different depending on the time of day.
The key where meal planning is concerned is you won’t know where you’re going if you don’t know where you’re starting — test your blood glucose before meals.