Concentrate on carbohydrates
Regular meals spaced through the day spread carbohydrate intake and help control and stabilise blood glucose. A regular eating pattern is of particular importance for people on insulin or taking insulin secretagogues (sulphonylureas or repaglinide) to reduce the incidence of hypoglycaemia. The current recommended carbohydrate intake is 50–55% of total daily energy. Carbohydrate foods should form the basis of each meal or snack. Studies in people with type 2 diabetes have shown that high carbohydrate diets reduce cholesterol concentration, improve glycaemic control and enhance insulin sensitivity.

Some researchers have suggested that the levels of carbohydrate recommended should be reduced and there should be higher protein or mono-unsaturated fat intake. Until more evidence is available, the authors suggest we stick with the currently accepted recommended levels for carbohydrate intake.

A sample meal plan (Table 4) can help patients develop a regular eating pattern. Some patients will require a midmeal snack, eg. some of those on insulin, but snacking should not be encouraged for those who are overweight or obese.

The glycaemic index (GI) of foods should be considered if blood glucose before meals are on target, but with hyperglycaemia after meals or hypoglycaemia between meals. Carbohydrate foods that break down slowly release glucose gradually into the blood and have a low GI.

Carbohydrate foods that produce a faster and higher rise in blood glucose levels have a high GI (Figure 3). A GI checklist (Table 5) may assist individuals to identify high GI foods in their diets and substitute lower GI alternatives.