Dietary total flavonoids intake and risk of mortality from all causes and cardiovascular disease in the general population: A systematic review and meta-analysis of cohort studies

Scope: Epidemiologic studies assessing the association between dietary total flavonoids intake and the risk of mortality from cardiovascular disease (CVD) and all causes have yielded inconsistent results. Therefore, we conducted a dose-response meta-analysis to investigate this association. Method and results: We searched PubMed and Embase databases from January 1966 through May 2016 and examined the references of retrieved articles to identify relevant prospective cohort studies. The random-effect model was used to calculate the summary risk estimates and dose-response analysis was performed. Ten studies were included in the present meta-analysis. The relative risk (RR) of all-cause mortality for the highest versus lowest category of total flavonoids intake was 0.82 (95% confidence interval (CI): 0.72-0.92). Dose-response analysis showed that those consuming 200 mg/day of total flavonoids had the lowest risk of all-cause mortality. Furthermore, a marginally significant association was found between dietary total flavonoids consumption and risk of death from CVD (summary RR: 0.85; 95% CI: 0.70-1.03; P = 0.099) and coronary heart diseases (summary RR: 0.74; 95% CI: 0.54-1.02; P = 0.069), respectively. Conclusion: The meta-analysis provides strong evidence for the recommendation of consuming flavonoids-rich food to reduce risks of mortality from all causes as part of a healthy diet among general adults.