Effect of Dietary PUFAs and Antioxidants on Antioxidant and Anti-Inflammatory Functions of HDL in a Cohort of Women

High-density lipoproteins (HDLs) protect against atherosclerosis through their antioxidant, anti-inflammatory, and other beneficial properties. Although interest is increasing in uncovering both physiological and external factors that influence these functions, definitive evidence remains lacking in this area. To fill this gap, we assessed for the first time how intake of saturated and unsaturated fatty acids and dietary antioxidants affects key HDL-associated proteins. We observed that myeloperoxidase (MPO) activity, a marker of HDL oxidation, was inversely correlated with total polyunsaturated fatty acids (PUFAs), omega-3 and omega-6 intake (p < 0.05), polyphenols (p < 0.001), and overall antioxidant capacity (p < 0.05). Levels of lipoprotein-associated phospholipase A2 also decreased with higher antioxidant consumption (p < 0.05). By contrast, glutathione peroxidase 3 (Gpx3) activity, a protective HDL enzyme, increased in tandem with omega-3 and antioxidant intake. Finally, a composite HDL-antioxidant/anti-inflammatory score integrating all measured proteins rose in association with total PUFAs (p < 0.001), omega-6 (p < 0.001), omega-3 (p < 0.01), polyphenols, and total antioxidants (p < 0.05). These findings suggest that higher dietary PUFA, especially omega-6, and antioxidant intake may enhance HDL’s atheroprotective properties.