Maryam Majdi

and 4 more

Background: Understanding the association between water consumption and mortality is important for guiding consumers and prioritizing dietary guidelines to reduce the risk. Therefore, in the current study, we conducted a systematic review and dose-response meta-analysis of prospective cohort studies to summarize the association between total water and drinking intake and risk of mortality from all causes and CVD. Method: A comprehensive search was performed on PubMed/Medline, Scopus, and ISI Web of Science up to February 2020. The random effects model was used to calculate pooled effect size (EFs) and 95% confidence interval. Result: Seven prospective cohort studies with a total of 116816 reporting 14754 cases of all-cause mortality and 7611 of CVD mortality, were included in the present meta-analysis. No significant association was found between drinking water intake and all-cause mortality (EFs: 0.82; 95% CI: 0.63-1.08, P=0.65) and CVD mortality (EFs: 0.82; 95% CI: 0.63-1.08, P= 0.16). Total water intake was not associated with all-cause mortality (EFs: 0.95; 95% CI: 0.83-1.09, P=0.47). However, indicating a significant inverse association between total water intake and risk of CVD mortality (EFs: 0.84; 95% CI: 0.77-0.93, P<0.001). Linear dose-response meta-analysis revealed a significant inverse association between total water intake and all-cause mortality by an additional one cup per day (Pooled ES: 0.98; 95% CI: 0.97-0.99, P= 0.001). Furthermore, each additional cup of total water intake per day was associated with a 3% lower risk of death from CVD (Pooled ES: 0.97; 95% CI: 0.96-0.98, P<0.001). Conclusion: High consumption of total water is associated with a lower risk of CVD mortality. However total water intake was not associated with an increased risk of all-cause mortality.