Abstract
A recent animal study suggested that olive oil or other oleic acid-enriched food sources promote adiposity. In contrast, human evidence indicates neutral or protective effects on weight gain. Reconciling these divergent findings is crucial for understanding the role of olive oil, specifically oleic acid, in metabolism. In this Perspective, we contrast the animal study with evidence in humans, emphasizing the context in which each body of research was generated. We also highlight key limitations for translating results from controlled animal experiments to humans. Olive oil, beyond being a traditional culinary fat, serves as a major dietary source of monounsaturated fatty acids in Mediterranean-style diets, where its consumption has been consistently linked to favorable metabolic profiles. Our Perspective emphasizes the need for comprehensive metabolic phenotyping in mice, which can facilitate translation to humans.
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JEG conceived the Perspective, performed the literature search and analysis, and drafted the manuscript. MAMG led the identification and appraisal of epidemiological literature in humans and contributed to revisions. RFV contributed to the analysis and interpretation of mouse data and revised the manuscript. All authors approved the final version and are accountable for all aspects of the work.
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Galgani, J.E., Fernández-Verdejo, R. & Martínez-González, M.A. Role of olive oil in weight gain: contrasting the animal and human findings. Eur J Clin Nutr (2026). https://doi.org/10.1038/s41430-026-01722-5
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DOI: https://doi.org/10.1038/s41430-026-01722-5
