Association between dietary patterns and visceral fat obesity in Japanese adults with normal body mass index

Background and objectives: Dietary factors contributing to visceral fat accumulation have not been clarified in Japanese people with an abdominal circumference of ≧85 cm for men and ≧90 cm for women, although their body mass index (BMI) is normal. Therefore, this study clarified factors contributing to visceral fat accumulation from the dietary patterns of Japanese people with normal BMI. Methods: In this study, 3,972 men and 2,929 women aged 39-74 years were included. They were participants in the Yamagata cohort with a normal BMI and completed a validated food frequency questionnaire (FFQ). Dietary patterns were extracted using cluster analysis from the intake of 19 food groups calculated from the FFQ. Further, the association between dietary patterns and visceral fat accumulation was evaluated by logistic regression analysis. Results: The following three dietary patterns were identified for men: "rice" (n = 1,831), "side dishes" (n = 502), and "bread, noodles, coffee, and alcoholic beverages" (n = 1,639), and the three dietary patterns identified for women were as follows: "side dishes" (n = 145), "rice and bread" (n = 1,654), and "noodles and milk" (n = 1,130). The number of men with visceral fat accumulation for each dietary pattern was 418 (22.8%) for "rice", 127 (25.3%) for "side dishes", and 483 (29.5%) for "bread, noodles, coffee, and alcoholic beverages". The number of women with visceral fat accumulation that selected "side dishes" was 5 (3.4%), "rice and bread" was 68 (4.1%), and "noodles and milk" was 51 (4.5%). Logistic regression analysis adjusted for age, smoking habits, dietary energy intake, breakfasting habits, snacking habits, eating speed, and daily walk durations showed that the odds ratio of visceral fat accumulation in the "bread, noodles, coffee, and alcoholic beverages" pattern was significantly higher than that of the "rice" pattern for men. In contrast, there was no significant association between dietary patterns and visceral fat accumulation in women. Conclusions: In men with normal BMI, dietary patterns with high consumption of bread, noodles, coffee, and alcoholic beverages may be associated with increased risk of visceral fat accumulation.