The Effect of Oleic Acid Enriched Diets on Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis Publisher



Xu H ; Xu X ; Sohouli MH
Source: Nutrition and Metabolism Published:2026

Abstract

Background: High-oleic diets (HODs), have been proposed to improve lipid and glucose metabolism, yet clinical evidence remains inconsistent. This systematic review and meta-analysis aimed to quantitatively evaluate the effects of HODs compared with low-oleic diets (LODs) on lipid profiles, apolipoproteins, and glucose homeostasis in adults. Methods: Following PRISMA 2020 guidelines, PubMed, Web of Science, Scopus, and Embase were searched from inception to September 2025. Randomized controlled trials (RCTs) in adults were included if the intervention provided ≥ 70% oleic acid of total fatty acids and differed from control diets by ≥ 5% points in oleic acid content. Data were pooled using random-effects models to estimate weighted mean differences (WMDs) with 95% confidence intervals (CIs). Results: Twenty-six RCTs (n = 1,244 participants) met the inclusion criteria. Compared with LODs, HODs significantly reduced total cholesterol (WMD: −0.13 mmol/L; 95% CI: −0.24 to − 0.01) and low-density lipoprotein cholesterol (LDL-C) (WMD: −0.11 mmol/L; 95% CI: −0.20 to − 0.01) and modestly increased Apo A1 (WMD: 0.02 mmol/L; 95% CI: 0.00 to 0.03). No significant changes were observed for high-density lipoprotein cholesterol (HDL-C), triglycerides, very low-density lipoprotein cholesterol (VLDL-C), Apo B, and glucose metabolism. Subgroup and meta-regression analyses indicated stronger lipid-lowering effects when ≥ 80% of total fatty acids were oleic acid. Also, low heterogeneity was reported for most variables. Conclusion: High-oleic dietary interventions modestly improve circulating lipid profiles, particularly total and LDL cholesterol, without adverse effects on glucose metabolism. The proportion of oleic acid intake appears to be a key determinant of metabolic benefit. © The Author(s) 2026.