High-carbohydrate and fibre diets in the treatment of diabetes

Abstract

After Kinsell and collaborators (1970) demonstrated a smaller glycaemic rise in diabetic subjects given larger rather than smaller nutrient loads (because of the more complicated composition of the intakes) notions that one can usefully prescribe diabetic diets from crude chemical composition of foods 'on the shelf have been abandoned, with greater consideration of the varied gastro-intestinal handling of foods, how they are changed by cooking, etc., the way different foods interact within the gastro-intestinal tract, and the importance of specific chemical constitution, both of the classical nutrients as well as fibre contents.

In practice, high-carbohydrate diets are usually entwined with high-fibre intake. Apart from the observations on the practicability of high-carbohydrate diets in obtaining successful glycaemic control of diabetics outside the 'First World, doubts were voiced in the late 1920s concerning the wisdom of the high-fat intake accompanying low-carbohydrate diets. In the next decade Himsworth showed in normal subjects that high-carbohydrate intake improved glucose tolerance, and this has been repeated in Seattle.

Data concerning complete meals or, much better, dietary regimes persisted with over long periods of time are more relevant than those from single intakes of liquid homogenates. We present observations on 6-week intakes of particular dietary regimes (in freeliving patients) from which the main conclusions would seem:

1) a high-carbohydrate intake does no harm to glycaemic control in diabetics, providing it is predominantly of polysaccharides;

2) a high-fibre intake has various beneficial effects, and in particular high viscous fibre intake reduces post-prandial glycaemia; and

3) either through some such effects, or just through reduction in fat intake because of increased carbohydrate, plasma lipid levels are benefited by high-carbohydrate regime.