Insulin and glucose in treatment of cardiogenic shock.

SIR,-Those of us who have worked in Africa when diabetes appeared to be uncommon must congratulate Dr. A. C. B. Wicks and Professor J. J. Jones (31 March, p. 733), who have extended the observations of other doctors' in Salisbury, Rhodesia. They are beginning to elucidate the role of refined carbohydrates as a factor in the pathogenesis of diabetes mellitus. If one wishes to state the degree of refinement of any starchy carbohydrate, it is desirable to record the crude fibre content; thus maize meal, such as that consumed by Africans in Rhodesia, might vary in crude fibre content from 0 7 g/ 100 g if of 60% extraction to 1 5 g/100 g if of 96% extraction. That of wheat wholemeal 100% extraction is 20 g/100 g, while white flour 70%, extraction has only a trace,2 probably a crude fibre content of about 0 1 g/ 100 g. It would be helpful if investigators could state the degree of extraction of the maize meal consumed in Rhodesia. In South Africa a recent analysis reported that Bantu preferred maize meal 80%' extraction (crude fibre 14 g/100 g), or 60%,, extraction (crude fibre 0:8 g/ 100 g).' Reports of the experimental production of diabetes mellitus in small rodents seldom mention the crude fibre content of the food offered, though tables2 can often supply these figures. Interpretation has been that excessive calorie intakes encourage obesity and hyperglycaemia. This is correct, but a more comprehensive appraisal of the situation suggests that diets rich in undigested fibre have different satiety mechanisms because a larger proportion of the food remains undigested in the bowel; less is consumed. When an animal feeds on its traditional food, fed ad libitum, it seldom becomes obese or develops diabetes. Perhaps man has a similar response, for refined starchy carbohydrates have not been his traditional food in Africa or in the Western World.-I am, etc., HUGH TROWELL Woodgreen, near Fordingbridge, Hants