Abstract
In prescribing a diabetic diet more attention has traditionally been paid to the amount of dietary carbohydrate than to its type or structure. We have compared the effect on blood glucose of substituting unrefined, whole foods for refined, processed foods in liberal carbohydrate diets (50-55% of dietary energy) eaten by 10 diabetic children in a randomised crossover study. All measurements were made at home. The unrefined diet used whole foods (including) dried beans) supplying 60 g/day of dietary fibre. The refined diet used processed foods supplying 20 g/day of dietary fibre. Diets were isocaloric for carbohydrate, fat, and protein. Glycaemic control was assessed by daily urine analysis for glucose, home blood glucose measurements, glycosylated haemoglobin, and by a 24-hour profile of blood and urinary glucose carried out at home after 6 weeks on each diet. Glycaemic control was significantly better on the unrefined diet. On profile days mean blood glucose levels on the unrefined and refined diets respectively were: preprandial: 5.5 and 8.4 mmol/l; postprandial 8.5 and 12.2 mmol/l. The mean 24-hour urinary glucose excretion on the unrefined diet was 9.3 g and on the refined diet was 38.0 g. Six months after the study the children were eating appreciably more dietary fibre than before (mean increase 13.6 g/day). Attention to food type and structure can improve blood glucose control in diabetic children and should provide an acceptable and more rational basis for dietary prescription than one based on carbohydrate quantity alone.