Abstract
BACKGROUND: Although metabolic syndrome (MetS) is associated with an increased risk of various cancers, the combined impact of MetS and healthy lifestyle factors (HLF) on cancer risk is unclear. This study aimed to investigate the independent and combined effects of MetS and HLF on the risk of 16 site-specific cancers in a large community-based cohort. METHODS: A total of 289,557 participants in the UK Biobank were analyzed. MetS was defined using a combination of metabolic factors, while HLF scores were evaluated based on lifestyle behaviors, such as smoking, alcohol consumption, physical activity, and diet. Cox proportional hazard models were used to investigate the relationship between MetS or HLF and cancer risk, adjusting for age, sex, ethnicity, education level, family history of cancer, and the Townsend Deprivation Index (TDI). RESULTS: During a median follow-up of 11.69 years, 11,190 individuals developed cancer. MetS was associated with an increased risk of 9 cancers in men and 7 cancers in women. Compared with participants with unfavorable lifestyles, regardless of metabolic status, HLF was significantly associated with decreased risk of overall cancer (without MetS: HR: 0.812; 95% CI: 0.745-0.886 for intermediate lifestyle and HR: 0.757; 95% CI: 0.669-0.855 for favorable lifestyle; with MetS: HR: 0.702; 95% CI: 0.572-0.862 for favorable lifestyle) and oesophagus, stomach, liver, lung, bronchus, trachea cancers in men and of lung, bronchus, trachea cancers in women. Our analysis demonstrated that the protective association between HLF and reduced cancer risk was confined to subgroups without MetS. Specifically, this association was observed for cancers of the lip, oral cavity, pharynx, colon, rectum, pancreas, kidney, bladder, and lymphoid leukemia in men, and for overall cancer in women(HR: 0.917; 95% CI: 0.862-0.975 for intermediate lifestyle and HR: 0.875; 95% CI: 0.817-0.938 for favorable lifestyle). CONCLUSION: MetS elevates risks for multiple cancers, while adopting a healthy lifestyle reduces risks of oesophagus, stomach, and lung, bronchus, trachea cancers in men and lung, bronchus, trachea cancer in women, regardless of metabolic status. However, MetS counteracts lifestyle-mediated protection against specific cancers-including lip, oral cavity, pharynx, colon, rectum, pancreas, kidney, and bladder cancers in men, as well as pancreas and breast cancers in women. These findings underscore the necessity to develop metabolic status-stratified management strategies and implement proactive prevention of MetS.