INDONESIAN TRADITIONAL FERMENTED FOODS AND IRON STATUS IN ADOLESCENT GIRLS: A NARRATIVE REVIEW OF MECHANISMS AND AVAILABLE EVIDENCE

Abstract

Anemia remains a major public health problem among Indonesian adolescent girls, with a national prevalence of 18% in the 2023 Indonesian Health Survey (SKI) and higher figures in the 2018 Basic Health Research (Riskesdas). Compliance with iron-folic acid supplementation remains difficult to sustain, keeping interest alive in food-based strategies that complement existing programs. Among the options available in Indonesia are traditional fermented foods, tempeh, dadih, tape, and oncom, whose fermentation processes are known to alter mineral bioavailability, though their specific contribution to adolescent iron status has received comparatively little attention. This narrative review brings together the scientific evidence and biological mechanisms linking Indonesian fermented foods to iron bioavailability and status, focusing on adolescent girls, drawing on PubMed, Google Scholar, and Scopus for openly accessible studies published between 2016 and 2026. Three mechanisms recur across the evidence: microbial phytase activity lowers phytate content, lactic acid bacteria reduce luminal pH and favor conversion of ferric to ferrous iron, and anti-inflammatory effects may lower hepcidin-mediated suppression of iron absorption. Tempeh carries the strongest support, with several small Indonesian studies linking tempeh-based products to higher hemoglobin levels in anemic adolescent girls. The case for dadih, tape, and oncom remains biologically plausible but rests mainly on mechanistic or preclinical data; dadih from Riau has yet to be tested against any iron-related outcome. Taken together, these fermented foods offer a culturally familiar, affordable complement to existing anemia-control efforts, though confirming their efficacy and establishing effective doses will require well-designed randomized controlled trials in Indonesian adolescent populations.