Dietary patterns in a high-risk population for glucose intolerance. Japanese-Brazilian Diabetes Study Group

We evaluated dietary habits as risk factor for glucose intolerance in a high risk population of Japanese-Brazilians enrolled in a study on the prevalence of diabetes (DM). Based on oral glucose tolerance test and WHO criteria, 331 had normal tolerance (NGT), 88 impaired tolerance (IGT) and 83 had type 2 DM (51 self-reported, 32 newly diagnosed diabetics). Clinical, laboratory and dietary data, assessed by food frequency questionnaire (FFQ), were compared between the NGT group and another composed of IGT and newly diagnosed DM (disturbed glucose tolerance or DGT group). Associations of total energy intake and nutrient intakes with glucose intolerance were analyzed by logistic regression. Also, subjects with NGT and DGT entered into separate models of multiple linear regression including BMI as the dependent variable, and total energy intake or each nutrient as independent variables. DGT group showed higher waist-to-hip ratio, blood pressure, plasma glucose and insulin levels and worse lipid profile. Total energy intake, macronutrients, fibers, alcohol and saturated fat intakes did not differ between groups; DGT was not associated with any nutrient intake in multivariate analyses. BMI of the subjects with DGT but not with NGT was associated with protein and cholesterol intakes in linear regression analysis. Our findings did not support an association between nutritional factors and glucose intolerance even in subjects who are unaware of their DGT, using FFQ to reflect current habits. However, we suggest that protein and cholesterol intakes may be markers of increased BMI. Despite assuming that obesity and insulin resistance precedes DM, FFQ may not be useful in the assessment of unfavorable dietary patterns among subjects at risk for glucose intolerance, such as Japanese-Brazilians with elevated BMI.