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Introduction Dietary extracellular vesicles (EVs) have emerged as bioactive mediators of systemic signalling. Bovine milk-derived extracellular vesicles (bMEVs) are stable during digestion, bioavailable, and capable of delivering functional cargo across species. While epidemiological evidence links dairy consumption with improved cardiovascular function, the direct effects of bMEVs on cardiac cells and tissues remain poorly defined. We hypothesised that bMEVs are taken up by cardiac cells and exert context-dependent cardioprotective effects.Methods bMEVs were isolated from commercially available bovine milk using differential ultracentrifugation and characterised according to MISEV 2023 guidelines (TEM, NTA, EV marker profiling). Cellular uptake was assessed in human induced pluripotent stem cell–derived cardiomyocytes (hiPSC-CMs), human cardiac fibroblasts, and hypertrophic cardiomyopathy–derived myofibroblasts using DiI-labelled bMEVs ( figure 1a). Cardiomyocyte viability, metabolism, and function were assessed under basal conditions and following hypoxia–reoxygenation injury (figure 1b). In vivo biodistribution and cardiac retention were evaluated in mice using DiR-labelled bMEVs administered via intramyocardial and intracardiac routes, followed by whole-organ imaging and cryosectioning. Proteomic profiling of bMEVs was performed using LC–MS/MS.Results bMEVs displayed typical EV morphology and size (30–200 nm) with enrichment of canonical EV markers. bMEVs were efficiently internalised by cardiomyocytes and cardiac fibroblasts. bMEV treatment was non-toxic to hiPSC-CMs and preserved contractile function, while attenuating proliferative and metabolic activity in myofibroblasts. Pre-treatment with bMEVs significantly improved cardiomyocyte viability following hypoxia–reoxygenation injury in a dose-dependent manner. In vivo, bMEVs demonstrated robust cardiac tissue uptake and retention for up to 24 hours, with evidence of uptake by cardiomyocytes and cardiac fibroblasts. Proteomic analysis revealed enrichment of proteins with established roles in cardioprotection, angiogenesis, oxidative stress regulation, and tissue repair, including MFGE8, ANXA2, CD36, SOD1, and heat shock proteins.Conclusions/Implications These findings demonstrate that bMEVs are bioavailable, taken up by cardiac cells and tissue, and exert context-dependent cardioprotective effects. bMEV cargo provides biological plausibility for direct modulation of cardiac remodelling pathways. Collectively, this work establishes bMEVs as functionally active dietary EVs with translational potential in cardiovascular health and disease.