Do everyday foods like yogurt and chocolate silently shape our lifespans? A comprehensive global analysis reveals which fermented foods may be associated with longevity and lower disease risk.
Research: Fermented food intake, all-cause and cause-specific mortality: A meta-analysis of prospective cohort studies. Image credit: Sweet Marshmallow / Shutterstock
In a recent study published in the journal Frontiers of nutritionresearchers evaluated whether consumption of fermented foods was associated with reduced all-cause and cause-specific mortality in healthy adults.
Health benefits of fermented foods and research gaps
What if everyday foods like yogurt, cheese, and even chocolate could affect our longevity? Fermented foods are a major part of the world’s diet, accounting for up to 27% of daily caloric intake in some people. These foods provide bioactive compounds, microbial metabolites, and probiotic microorganisms that support gut health and immune function and may reduce the risk of chronic disease.
However, existing research shows conflicting evidence regarding the effects of fermented foods on cardiovascular disease and cancer. Much of the available evidence focuses primarily on fermented dairy products, highlighting the need for broader analyzes including diverse food types and populations.
Meta-analysis methods and study selection criteria
This study was conducted in accordance with the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A systematic literature search was conducted using PubMed, Scopus, and Cochrane databases to identify prospective cohort studies on fermented food consumption and mortality.
This search initially included studies through March 2023 and was subsequently updated through March 2025. Outcomes of interest included all-cause mortality, cardiovascular disease, and cancer-related mortality.
Eligible studies included healthy adult populations and excluded studies involving pre-existing conditions, pregnancy, early childhood, or interventions with probiotics or fermented alcoholic beverages. A structured selection process using the Population, Intervention, Outcome (PIO) framework ensured consistency. Data extracted included participant characteristics, number of deaths, follow-up period, and dietary exposure levels.
Study quality was assessed using the Newcastle-Ottawa Scale (NOS). Random effects meta-analysis using log-transformed estimates accounted for heterogeneity. Effect sizes were reported as hazard ratios (HRs) or risk ratios (RRs) derived from relative risks comparing high and low intake groups. Sensitivity analysis, heterogeneity testing, and publication bias assessment were also performed.
Consumption of fermented foods and mortality consequences
The meta-analysis included 50 prospective cohort studies with more than 3 million participants. The results showed that while some fermented foods were associated with a lower risk of death, other fermented foods showed no significant association.
Fermented dairy products such as yogurt were strongly associated with lower mortality. Higher intakes were shown to reduce the risk of all-cause mortality by approximately 6%. Daily intake was also associated with reduced cardiovascular mortality (RR = 0.932) and cancer mortality (RR = 0.940). These associations may be mediated by mechanisms such as modulation of the gut microbiota, anti-inflammatory effects, and improved metabolic health.
Yogurt consumption was associated with lower all-cause mortality (RR = 0.933), but the associations with cardiovascular disease and cancer mortality were not statistically significant.
Cheese consumption showed a small reduction in all-cause mortality (RR = 0.970), but no significant association with cardiovascular disease or overall cancer mortality was found. A potential protective effect on lung cancer mortality was observed.
Chocolate consumption was associated with decreased all-cause mortality (RR = 0.901) and cardiovascular mortality (RR = 0.843). These effects may be related to cocoa polyphenols, which improve vascular function and reduce oxidative stress, but residual confounding cannot be excluded.
In contrast, miso intake showed no consistent association with all-cause mortality. The protective effects reported in women in single studies are limited and may reflect population-specific factors. Overall, no strong association was found between miso or bread intake and outcome.
Although results were consistent across sensitivity analyses, heterogeneity was observed due to differences in population characteristics, dietary patterns, and study design. Although most analyzes did not show significant publication bias, some subgroup analyzes suggested potential bias and should be interpreted with caution.
Conclusion on fermented foods and longevity
This meta-analysis suggests that increased intake of certain fermented foods, particularly fermented milk, yogurt, cheese, and chocolate, is associated with decreased all-cause and cardiovascular mortality. Fermented milk also showed an association with lower cancer mortality.
However, these findings are based on observational data and do not establish a causal relationship. The results also highlight that not all fermented foods have the same effects and highlight the importance of food type, composition, and fermentation process.
