Fermented foods consumption, all-cause, and cause-specific mortality: a meta-analysis of prospective cohort studies.

Purpose: Fermented foods are widely consumed, contribute important bioactive compounds and microbial metabolites to the diet, and play an important role in global nutrition. This meta-analysis evaluated evidence from prospective cohort studies on the association between fermented food and non-alcoholic beverage consumption and the risk of all-cause and cause-specific mortality in healthy adults. Methods: A systematic search of three databases identified 50 cohort studies, including more than three million participants, examining associations between fermented food intake and all-cause, cardiovascular disease (CVD), and cancer mortality. Risk of bias was assessed using the Newcastle-Ottawa Scale. Random-effects meta-analyses using the DerSimonian and Laird method, were conducted on fully adjusted risk estimates comparing highest vs. lowest intake categories. Results: Higher consumption of chocolate, cheese, and fermented milks (including yogurt) was associated with lower all-cause and CVD mortality. Fermented milk consumption also showed a protective association with cancer mortality. Miso and bread consumption showed no significant associations with mortality. Conclusion: This is the first meta-analysis to comprehensively evaluate the association between fermented food intake and mortality. Findings support a protective role for specific fermented foods consumption, i.e., milks, cheese, and chocolate, against all-cause and CVD mortality, with additional evidence of a protective effect of fermented milk on overall cancer mortality. These associations may underline the role of bioactive peptides, polyphenols, and microbial metabolites that modulate the gut microbiota, improve vascular function, and reduce the risk of certain chronic diseases. Systematic review registration: https://osf.io/vg7f6, identifier: vg7f6.