Gender-specific associations of diet quality and dietary patterns with metabolic syndrome: evidence from Korea National Health and Nutrition Examination Survey (KNHANES) VI

BACKGROUND: The prevalence of metabolic syndrome (MetS) is increasing in Korea, yet optimal dietary intervention strategies remain unclear. This study compared the effectiveness of an overall diet quality assessment with culture-specific dietary patterns in preventing MetS among Korean adults. METHODS: We analyzed data from 12,317 Korean adults (20–64 years) from KNHANES-VI (2013–2017), after excluding pregnant women and participants with incomplete demographic, health, or nutrition survey data. Diet quality was assessed using the Korean Healthy Eating Index (KHEI). Three dietary patterns were identified through factor analysis: Korean-style diet (KSD), Western-style diet (WSD), and high-rice diet (HRD). Multivariable logistic regression models estimated MetS associations with dietary factors after adjusting for demographic, socioeconomic, and lifestyle variables, with gender-stratified analyses. RESULTS: Gender-specific differences emerged in the associations of dietary quality with MetS risk. Women in the highest KHEI tertile had 29% lower ORs of MetS risk compared to the lowest tertile (OR = 0.71; 95% CI: 0.54–0.94), while no significant association was observed in men. In contrast, dietary patterns showed similar associations with MetS in both genders: WSD and HRD were positively associated with MetS (OR range: 1.17–1.65), and these associations attenuated after lifestyle adjustment. KSD demonstrated favorable nutrient profiles, but no significant association with MetS in either gender. CONCLUSIONS: Diet quality indices predicted MetS risk in women but not men, while dietary patterns were associated with metabolic disorders in both genders. These findings suggest that pattern-based dietary approaches may offer practical advantages for population-level MetS prevention strategies, with potential benefits for gender-specific intervention design. Further longitudinal and intervention studies are needed to confirm these cross-sectional observations.