A Mediterranean‐style low glycemic load diet reduces LDL oxidation and Lipoprotein (a) in women classified with the metabolic syndrome

Abstract

We evaluated the effect of a Mediterranean‐style low glycemic load diet alone (n = 17) or accompanied by intake of a medical food containing plant sterols, soy protein, rho iso‐alpha acids, and proanthocyanidins (n = 20) on oxidized LDL (oxLDL), a key marker of oxidative stress and on Lipoprotein (a) [Lp (a)], a marker of atherosclerosis and thrombosis in women classified with metabolic syndrome. As diets high in trans fatty acids have been associated with increased Lp(a), we evaluated change in trans fatty acid intake over the 12 weeks of study and found reduction from 5.1 ± 3.0 g/d to 1.5 ± 1.2 g/d (P< 0.001). Plasma LDL cholesterol (P < 0.0001) decreased substantially as did small dense LDL from 1127 ± 446 mmol/L to 939 ± 434 mmol/L (P < 0.00001) measured by nuclear magnetic resonance. Measurements of oxLDL are based on the recognition of oxidized apo B100 by monoclonal antibody 4E6. Although plasma levels of oxLDL had a wide range among subjects (1–745.8 ng/mL), this parameter was decreased over time for all women from 121.3 ± 150.4 to 110.7 ± 153.9 ng/mL (P < 0.025) with no differences between groups. In addition, Lp (a) decreased from 24.2 ± 20.8 mg/dL at baseline to 10.6 ± 5.7 mg/dL at wk 12 (P < 0.01). Thirty percent of the women had plasma Lp(a) concentrations > 30 mg/dL, which returned to normal range after 12 wk of dietary intervention.. These data suggest that dietary modifications involving reduced intake of trans fatty acids and resulting in the formation of less atherogenic lipoproteins have an impact on plasma oxLDL and Lp(a). [Supported by MetaProteomics, LLC].