Association of the dietary-behavioral risk index with metabolic syndrome and its components: a cross-sectional study in rural China.

BACKGROUND: Metabolic syndrome (MetS) has become a growing public health concern. However, systematic assessment of combined lifestyle and multidimensional dietary factors in rural Chinese populations remains limited. This study aimed to investigate the associations of an obesity-centered lifestyle score (OLS), Diet Quality Index-International (DQI-I), and a newly constructed dietary-behavioral risk index (DBRI) with MetS and its components in a rural Chinese population. METHODS: This cross-sectional study included 14,269 residents from the Northwest China Natural Population Cohort (CNC-NX). DBRI was constructed using the Alkire-Foster dual cut-off approach and categorized into quartiles. Spearman correlation and multivariate logistic regression were used to examine the associations of OLS, DQI-I, and DBRI with MetS. RESULTS: Both OLS and DBRI were positively correlated with MetS prevalence (both P<0.001). DBRI showed a significant dose-response association with MetS, with the highest quartile having an odds ratio of 2.61 (95% CI: 2.29-2.98) compared with the lowest. A nonlinear relationship was observed using restricted cubic splines (P for nonlinear=0.013), with a threshold effect near DBRI≈0.5. The total DQI-I score was not significantly associated with MetS. CONCLUSION: DBRI, a composite index integrating lifestyle and dietary quality, was significantly associated with MetS in a dose-response manner, suggesting its potential utility in risk stratification. Public health interventions should focus on dietary optimization and long-term promotion of obesity-related lifestyle habits.