INCIDENCE AND AETIOLOGY OF LACTOSE INTOLERANCE

Abstract

These investigations are in the nature of a pilot survey preliminary to a fuller study. The numbers studied were small and the conclusions reached must necessarily be tentative. Lactose tolerance tests were performed on 30 subjects—10 Caucasians, 10 Australian-born Chinese, and 10 overseas Chinese. Detailed subject histories were taken which paid special attention to milk consumption. The tests showed that there was no significant difference between the mean rises of blood sugar level of the Australian-born Chinese (16·9 mg/100 ml) and those of the overseas Chinese (13·4 mg/100 ml). The Caucasian group showed a rise (36 mg/100 ml) significantly higher than the other groups. In addition, nine Australian-born Chinese and seven overseas Chinese were considered to be Intolerant to lactose. On the other hand, no Caucasians were considered to be intolerant. Since the Australian-born. Chinese and the Caucasians share the same environment and have reasonably similar diets, it would seem that the aetiology of lactose intolerance is at least partly genetic.