Association of trans fatty acid intake with metabolic risk factors among free-living young Japanese women.

OBJECTIVE We examined cross-sectional associations of total, hydrogenated, and natural trans fatty acid intake with selected metabolic risk factors in young Japanese women. METHODS Subjects were 1136 Japanese female dietetic students aged 18-22 years. Dietary intake was estimated using a validated, self-administered diet history questionnaire. Associations between trans fatty acid intake and metabolic risk factors were examined with multivariate linear regression analysis, with control for potential covariates. Dietary covariates included intake of energy, total fat, and saturated fatty acids (model 1); monounsaturated fatty acids instead of saturated fatty acids (model 2); and polyunsaturated fatty acids instead of saturated fatty acids (model 3). RESULTS Mean (standard deviation) total trans fatty acid intake was 0.90% (0.30%) of total energy. Hydrogenated trans fatty acids contributed 77% of total trans fatty acid intake. Total trans fatty acid intake was significantly and positively associated with waist circumference, triacylglycerol, and glycated hemoglobin, except in the analysis of triacylglycerol with adjustment for monounsaturated fatty acids. No associations were found between total trans fatty acid intake and body mass index, cholesterol, or glucose. Hydrogenated trans fatty acid intake was significantly and positively associated only with waist circumference and glycated hemoglobin. No association was observed for natural trans fatty acid intake. CONCLUSION hydrogenated trans fatty acid intake was positively associated with several metabolic risk factors among free-living young Japanese women with relatively low intake.