Snacks are very important in the diet of insulin dependent diabetics, especially those on twice-a-day regimes, since calories must be provided at regular intervals to balance the  glucose lowering action of injected insulin.

For this reason diet prescriptions for those with IDDM usually specify 3 meals and 3 snacks. It is also a good idea for those with NIDDM on tablets to divide their calories throughout the day rather than to eat three large meals, which may require large surges of  insulin.
Timing of snacks is usually mid-morning, mid-after-noon, and pre-bed.

Calorie content and composition of the snack will vary with the total calorie allowance, and the dose and timing of’ insulin injections, as well as activity at different times of the day. For example, someone who is overweight may
need only a glass of skim milk as a mid-morning snack, whereas a thin adolescent may require a bowl of noodle or a tuna sandwich plus a glass of  milk.

On days when exercise is done after work, a large snack at mid-afternoon may be necessary to offset hypoglycaemia.

Diets for Diabetics with Special Nutritional Requirements

Nutrients Needs in Diabetics