The Relationship Between Consumption of Traditional Indonesian Fermented Foods and Mental Health Status in Indonesia: A Narrative Review

Abstract

Background: Mental health issues in Indonesia are increasing, with a depression prevalence of 1.4% reported in the 2023 Indonesian Health Survey. Indonesia also has a rich heritage of traditional fermented foods, including tempeh, dadih, tape, and oncom, which may influence mental health through the gut-brain axis. However, research specifically examining the relationship between traditional Indonesian fermented foods and mental health remains limited.

Objective: This narrative review aims to examine the scientific evidence linking the consumption of traditional Indonesian fermented foods with mental health status and identify the underlying biological mechanisms.

Materials and methods: A narrative review was conducted using literature published between 2020 and 2025. Literature searches were performed using PubMed/Medline, Google Scholar, and Scopus. Studies were selected based on their relevance to fermented foods, particularly traditional Indonesian fermented foods, bioactive components, mental health, cognitive function, depression, anxiety, and the gut-brain axis.

Results: Seven studies met the inclusion criteria, including controlled clinical trials, a literature review, an animal experimental study, a prospective cohort study, a quasi-experimental study, and a cohort meta-analysis. Overall, most studies indicated a potential positive relationship between fermented food consumption and mental health outcomes, with tempeh having the strongest scientific evidence among Indonesian fermented foods. The proposed mechanisms include modulation of neurotransmitters such as serotonin, GABA, and dopamine, reduction of neuroinflammation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. Tempeh consumption was associated with improved cognitive function and neuroprotective effects in older Indonesian adults. Evidence regarding dadih, tape, and oncom remains limited and is primarily based on mechanistic findings.

Conclusion: Traditional Indonesian fermented foods, particularly tempeh, show potential as a localized food-based approach to support mental health through the gut-brain axis. However, evidence for dadih, tape, and oncom remains limited. Further randomized controlled trials involving Indonesian populations are needed to establish causal relationships, determine effective consumption patterns, and support the integration of traditional fermented foods into nutrition policies.