Gender disparities in complex association of metabolic syndrome with dietary habits and lifestyle risk factors in Chinese population

The purpose of this study is to explore individual and joint effect of comprehensive dietary habits and lifestyle on Metabolic syndrome(MetS), and its gender disparities. Data were derived from the baseline survey in the Regional Ethnic Cohort Study in northwest China. Unhealthy lifestyle index(ULI) and unhealthy dietary habits score(UDHS) were established. The association of MetS and its components with ULI or UDHS was analyzed by logistic model. The joint impact of UDHS and ULI on MetS was investigated. Potential masking effect of lifestyle was evaluated on the association between dietary habits and MetS. All analyses were conducted separately by gender. ULI was associated with a higher risk of MetS and its components, irrespective of gender. In males, higher UDHS was linked to a higher risk of MetS while in females it appeared to be associated with a lower risk of MetS. Participants with unhealthy dietary habits and an unhealthy lifestyle were found to have a higher risk of developing MetS compared to those maintaining healthy dietary habits and lifestyle, with 3.18 times(95% CI: 2.48 ~ 4.08) higher risk in males and 3.36 times(95%CI: 2.27 ~ 4.97) higher risk in females. However, females with healthy dietary habits but unhealthy lifestyle showed a higher OR of 5.52. ULI masked a 41.7% effect between UDHS and MetS in females. Unhealthy lifestyle was significantly associated with increased risk of MetS regardless of gender. Unhealthy dietary habits appear to increase the risk of MetS in males but not females. The unhealthy lifestyle may interfere with effect of unhealthy dietary habits on MetS in females. Adherence to healthy lifestyle and dietary habits would benefit prevention and control of MetS.