Effects of dietary fibre supplementation in stable and labile insulin-dependent diabetics

Summary Seven stable and 10 labile insulin-dependent diabetic patients were submitted to 2 dietary regimens which were given in random order and maintained for 10 to 15 days. During one period (“control”) patients were given their usual diets. During the other period patients received a fibre supplemented diet (“test”). The fibre supplementation was calculated to provide 1 g dietary fibre per 15 g available carbohydrate. For each period, diabetic control was estimated from: (i) daily glycosuria; (ii) % glycosylated haemoglobin, (iii) insulin requirements, (iv) frequency of hypoglycaemic episodes and (v) circadian blood glucose levels. Dietary fibre supplementation resulted in: (i) decreased glycosuria in both stable (12.8±5.6 g/day vs 25.5±6.9 P < 0.01) and labile diabetics (35.8±10.5 g/day vs, 52.5±7.1, P < 0.02); (ii) a significant decrease in blood glucose at 1430h (P < 0.02) in stable and at 1430 h (P < 0.05) and 2030h (P < 0.01) in labile diabetics. The percentage of glycosylated haemoglobin was identical in stable (10.8±1.0%) and labile diabetics (10.7±1.0) and was slightly depressed with the fibre supplemented diet (9.5±0.8 and 9.3±0.6 respectively). The mean blood glucose during the control period was not significantly different in stable (186±28 mg/100 ml) and labile diabetes (221±24 mg/ 100 ml) and did not change significantly with fibre treatment. The results show that the control of stable and labile diabetes is improved to a similar degree by dietary fibre. This effect results mainly from a decrease in post prandial hyperglycaemia after lunch and dinner.