Abstract
BACKGROUND/OBJECTIVES: Metabolic syndrome (MetS) is closely connected to dietary and lifestyle factors, with diet being one of the primary risk factors for MetS, acting as a key factor in both prevention and management. In this study, we analyzed the mediating effect of the Korean Healthy Eating Index (KHEI) on the relationship between lifestyle patterns and MetS in middle-aged Koreans using data from the 2019-2021 Korea National Health and Nutrition Examination Survey (KNHANES). SUBJECTS/METHODS: This study examined data from 5,196 adults aged 40-64 yrs who participated in the eighth KNHANES. Data on 5 lifestyle factors-smoking, alcohol consumption, physical activity, sleep duration, and stress perception-were analyzed. The latent class analysis (LCA) was performed using Mplus 8.11, and SPSS PROCESS Macro v4.2 was used for statistical analysis to analyze the mediating effect of the KHEI. RESULTS: The model categorized lifestyle factors into three into 3 clusters: 'Low Activity Class,' 'Low Activity and Smoking Class,' and 'Multiple Risk Class.' The KHEI mediation analysis showed significant effects: 0.0205 (95% confidence interval [CI], 0.0062-0.0363) in the 'Low Activity and Smoke Class,' and 0.0420 (95% CI, 0.0133-0.0726) in the 'Multiple Risk Class.' The mediating effect of the KHEI domain "adequacy" was significant in these groups, with effects of 0.0357 (95% CI, 0.0184-00563) and 0.0662 (95% CI, 0.0364-0.6491), for the respective groups. Balance of energy intake was significant in the group with 'Multiple Risk Class' (0.0189; 95% CI, 0.0044-0.0378). CONCLUSION: The results suggest that a healthy diet improves health management and reduces risk factors for MetS. Nonetheless, better strategies for dietary improvement through a detailed analysis of KHEI components are warranted.