Dietary patterns and abdominal obesity in middle-aged and elderly Japanese adults: Waseda Alumni's Sports, Exercise, Daily Activity, Sedentariness and Health Study (WASEDA'S Health Study)

Abstract

Objective: The aim of this study was to investigate the associations between dietary patterns and abdominal obesity among middle-aged and elderly Japanese people, using both waist circumference (WC) and visceral fat (VF) as indices.

Methods: A cross-sectional study was conducted with 829 adults (534 men and 295 women), 40 to 79 y of age, who participated in the Waseda Alumni's Sports, Exercise, Daily Activity, Sedentariness and Health Study (WASEDA'S Health Study). Dietary patterns were derived from principal component analysis. VF was measured using magnetic resonance imaging. To examine the associations of each dietary pattern with WC and VF, we calculated multivariate-adjusted means and 95% confidence intervals (CIs) of WC and VF for the tertile of each dietary pattern score.

Results: Two main dietary patterns were identified: "healthy Japanese" and "seafood and alcohol." The healthy Japanese dietary pattern score was inversely associated with WC and VF in men only. WC measurements were 84.9 cm (95% CI, 83.7-86.1), 83.9 cm (95% CI, 82.7-85.1), and 82.4 cm (95% CI, 81.2-83.6); P_trend = 0.006, and VF measurements were 94.0 cm² (95% CI, 85.6-102.4), 89.4 cm² (95% CI, 81.1-97.7), and 80.4 cm² (95% CI, 72.5-88.4); P_trend = 0.027 for the lowest through the highest tertile of healthy Japanese dietary pattern scores in men. The seafood and alcohol dietary pattern was not associated with WC and VF.

Conclusion: The healthy Japanese dietary pattern was negatively associated with WC and VF in middle-aged and elderly Japanese men.

Keywords: Cross-sectional study; Diet; Principal component analysis; Visceral fat; Waist circumference.