Chili pepper intake and all-cause and disease-specific mortality

Background: Chili pepper has been used for the treatment and prevention of multiple diseases. This may be due to its abundance of bioactive components, such as carotenoids, which are well known for their antioxidant properties. To date, several prospective cohort studies have examined the association between chili pepper intake and mortality, but the results have not been consistent. This study aimed to clarify the association between chili pepper intake and all-cause and disease-specific mortality using a meta-analysis. Methods: PubMed, Embase, and ISI Web of Science databases were searched up to December 20, 2020, and reference lists of included studies were manually reviewed. All prospective cohort studies on the association between chili pepper intake and all-cause, cardiovascular disease (CVD)-specific, and cancer-specific mortality were included in this study. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated in the meta-analysis. Between-study heterogeneity was assessed using I² statistic and Q test. Results: A total of 4 cohort studies (N=564,748; all four studies had adjusted for important potential confounders such as demographic variables, dietary intake, and physical activity) were ultimately included in this meta-analysis. Among them, 31,527 died due to all causes, 10,184 died due to CVD, and 9,868 died due to cancer. Compared to none or rare consumption of chili pepper, consumption of chili pepper (ever or more than once a week) could significantly reduce the risk of all-cause mortality (summary adjusted HR: 0.87, 95% CI: 0.85, 0.90), CVD-specific mortality (summary adjusted HR: 0.89, 95% CI: 0.85, 0.93), and cancer-specific mortality (summary adjusted HR: 0.92, 95% CI: 0.88, 0.97). There was no significant between-study heterogeneity in the analyses (all-cause mortality: I²=0.7%, P=0.389; CVD-specific mortality: I²=21.8%, P=0.280; cancer-specific mortality: I²=0.0%, P=0.918). Conclusions: The present meta-analysis confirmed that chili pepper intake could reduce the risk of all-cause, CVD-specific, and cancer-specific mortality, suggesting that chili pepper may be a beneficial ingredient in the diets in prolonging life.