Higher ultraviolet light exposure is associated with lower mortality: an analysis of data from the UK Biobank cohort study

Abstract

ABSTRACTObjectiveTo examine to what extent UV exposure is associated with all-cause and cause-specific mortality.DesignProspective population-based study.SettingUK Biobank.Participants376,729 participants with white ancestry and no missing data. Two UV exposures were assessed: sun-seeking behaviour (categorised as less active versus more active) and home latitude.Main outcome measuresAll-cause, cardiovascular disease (CVD), cancer and non-CVD/non-cancer mortality. Risk of residual confounding was examined using three negative control outcomes.ResultsThe median follow-up was 12.7 years. Participants with more active sun-seeking behaviour were at a lower risk of all-cause mortality (HR=0.86; 95% confidence interval (CI) 0.80 to 0.93), CVD mortality (HR=0.81; 95% CI 0.68 to 0.95) and cancer mortality (HR=0.86; 95% CI 0.77 to 0.95) compared to participants with less active sun-seeking behaviours, adjusted for demographic, socioeconomic, behavioural and clinical confounders. More active sun seekers had around 50 extra days of survival. Participants whose home latitude was 300km farther south were also at a lower risk of all-cause mortality (HR=0.94; 95% CI 0.92 to 0.96), CVD mortality (HR=0.91; 95% CI 0.86 to 0.95) and cancer mortality (HR=0.93; 95% CI 0.90 to 0.96), adjusted for demographic, socioeconomic, behavioural and clinical confounders. Participants whose home latitude was 300km farther south had around 16 extra days of survival. Sun-seeking behaviour was not associated with two of the three negative controls and home latitude was not associated with any of the negative controls.ConclusionsGreater behavioural and higher geographically related UV exposures were associated with a lower risk of all-cause, CVD and cancer mortality. This study adds to growing evidence that the benefits of UV exposure may outweigh the risks in low sunlight countries. Tailoring public health advice to both the benefits and hazards of UV exposure may reduce the burden of disease and increase life expectancy in low sunlight countries.