The insulin pattern and quantity necessary for high-protein, high-fat (HPHF) meals are not well understood. The purpose of this study was to assess the amount and pattern of insulin necessary to maintain euglycemia for 5 hours after having an HPHF meal vs a low-protein low-fat (LPLF) meal. For one year, ten kids with type 1 diabetes were enrolled in this randomised crossover clinical study, which was performed at two Australian paediatric diabetes facilities. Participants were randomly assigned to either an HPHF or an LPLF meal with the same carbohydrate content. The insulin needs to sustain postprandial euglycemia for 5 hours were determined using a modified insulin clamp method. The HPHF meal had considerably higher total mean insulin needs than the LPLF meal. Extra IV insulin was necessary for HPHF: 0 to 2 hours after the meal and 4 to 5 hours afterwards. There were significant inter-individual variations in the amount of extra insulin and the pattern of insulin administration.

The addition of protein and fat to a standardised carbohydrate meal nearly doubled the mean insulin need, with most individuals requiring half of the extra insulin within the first two hours.