Diet and glucose tolerance in a Chinese population

Abstract

Background: Associations between dietary factors and glucose tolerance observed in Caucasian populations may not be applicable to Chinese populations, since the traditional Chinese diet contains plentiful vegetables and is rice-based (which has a lower glycemic index than potatoes). To address this question, the dietary patterns in 988 Hong Kong Chinese subjects with normal and impaired glucose tolerance, and diabetes, were examined in a cross sectional survey to determine if there is any association between diet and glucose tolerance. Method: A stratified random population sample of 988 subjects (488 male, 500 female) was recruited. A food frequency questionnaire was used to determine dietary intake, and glucose tolerance was examined using the glucose tolerance test and the WHO criteria used to classify subjects into the three glucose tolerance categories. Results: Using the standardized world population of Segi, the prevalence rate for DM was 6.6% for men and 5.7% for women; and for IGT 10.3% for men and 15.4% for women aged 30-64 y. Abnormal glucose tolerance is associated with female gender, older age, lower educational attainment and higher body mass index (BMI). No clear pattern of association with dietary factors was observed after adjusting for confounding factors. However, if subjects with BMI ≥ 25 kg/m 2 were excluded, an increase in mean consumption of rice/noodles/pasta per week was observed in the DM group, after adjusting for total energy intake and other confounding factors. No association between dietary variety, which has been linked with body fatness, and glucose tolerance, was observed. Conclusion: Dietary habit may not be a strong risk factor for the development of glucose intolerance in Chinese populations, given the favorable features of the Chinese diet. The high consumption of rice in the DM subjects who are of normal BMI suggests that further studies examining glycemic indices of Chinese food items may be beneficial. Obesity still remains the most important predisposing factor.