Prospective study of dietary mushroom intake and risk of mortality: results from continuous National Health and Nutrition Examination Survey (NHANES) 2003-2014 and a meta-analysis

Background: Whether mushroom consumption, which is a rich source of potent antioxidants ergothioneine and glutathione, vitamins, and minerals (e.g., selenium & copper), is associated with a lower mortality risk is not well understood. This study aimed to examine the association between mushroom consumption and risk of mortality in a prospective cohort study and a meta-analysis of prospective cohort studies. Methods: We followed 30,378 participants from the continuous National Health and Nutrition Examination Survey (NHANES) extant data (2003-2014). Dietary mushroom intake was assessed using up to two 24-h recalls. Mortality was evaluated in all participants linked to the National Death Index mortality data through December 31, 2015. We used Cox proportional hazards regression models to calculate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs). We also conducted a meta-analysis, including results from our present study and 4 other cohort studies. Results: During a mean (SD) of 6.7 (3.4) years of follow-up, a total of 2855 death cases were documented among NHANES participants. In our analysis of continuous NHANES, we found a non-significant association between mushroom consumption and all-cause mortality (adjusted hazard ratio (HR) = 0.84; 95% CI: 0.67-1.06) after adjusting for demographic, major lifestyle factors, overall diet quality, and other dietary factors, including total energy. The meta-analysis of prospective cohort studies, including 601,893 individuals, showed that mushroom consumption was associated with a lower risk of all-cause mortality (pooled risk ratio: 0.94; 95% CI: 0.91, 0.98). Conclusion: In a meta-analysis of prospective cohort studies, mushroom consumption was associated with a lower risk of all-cause mortality.