I have a question about how fast blood sugar rises when a person starts eating. I realize different foods are converted to blood sugar a different rates, but at this point, I am looking for a good rule of thumb, or if that is not wise, then a concise reference chart or something to go by.

The practical reason I am curious about this is I want to know when to bolus our son who just got on an insulin pump. He is on fast-acting insulin which starts working in five minutes. Is it a bad idea to wait until after the meal to give him the bolus? Our rationale is we can tailor the bolus to exactly how much he ate, but if his blood sugar is rising quickly, this may not be the optimum timing for the bolus.

Generally, it is wiser to have the insulin analogs (Humalog or Novolog) used as bolus insulins through an insulin pump administered just prior to food. However, we and others did a study which looked at non-pump treatment with analogs in prepubertal children and found that analogs given immediately after food worked almost as well as when given just prior to food. If you can estimate and have a child who eats reliably, then pre-food is probably best. If there are vagaries of food intake, as in many toddlers and some young children, then immediately after eating offers you most of the advantages of the analogs plus knowing exactly the quantity of foods consumed so there is less guesswork. The third group, those who received non-analog insulin 30 minutes prior to food had the worst postprandial blood glucose levels.

SB