Background-Epidemiological studies suggest that nut intake decreases coronary artery disease (CAD) risk. Nuts have a cholesterol-lowering effect that partly explains this benefit. Endothelial dysfunction is associated with CAD and its risk factors and is reversed by antioxidants and marine n-3 fatty acids. Walnuts are a rich source of both antioxidants and ␣-linolenic acid, a plant n-3 fatty acid. Methods and Results-To test the hypothesis that walnut intake will reverse endothelial dysfunction, we randomized in a crossover design 21 hypercholesterolemic men and women to a cholesterol-lowering Mediterranean diet and a diet of similar energy and fat content in which walnuts replaced Ϸ32% of the energy from monounsaturated fat. Participants followed each diet for 4 weeks. After each intervention, we obtained fasting blood and performed ultrasound measurements of brachial artery vasomotor function. Eighteen subjects completing the protocol had suitable ultrasound studies. Compared with the Mediterranean diet, the walnut diet improved endothelium-dependent vasodilation and reduced levels of vascular cell adhesion molecule-1 (PϽ0.05 for both). Endothelium-independent vasodilation and levels of intercellular adhesion molecule-1, C-reactive protein, homocysteine, and oxidation biomarkers were similar after each diet. The walnut diet significantly reduced total cholesterol (Ϫ4.4Ϯ7.4%) and LDL cholesterol (Ϫ6.4Ϯ10.0%) (PϽ0.05 for both). Cholesterol reductions correlated with increases of both dietary ␣-linolenic acid and LDL ␥-tocopherol content, and changes of endothelium-dependent vasodilation correlated with those of cholesterolto-HDL ratios (PϽ0.05 for all). Conclusions-Substituting walnuts for monounsaturated fat in a Mediterranean diet improves endothelium-dependent vasodilation in hypercholesterolemic subjects. This finding might explain the cardioprotective effect of nut intake beyond cholesterol lowering.

Eating competence (EC), a bio-psychosocial model for intrapersonal approaches to eating and food-related behaviors, is associated with less weight dissatisfaction, lower BMI, and increased HDL-cholesterol in small U.S. studies, but its relationship to nutrient quality and overall cardiovascular risk have not been examined. Prevención con Dieta Mediterránea (PREDIMED) is a 5-y controlled clinical trial evaluating Mediterranean diet efficacy on the primary prevention of cardiovascular diseases (CVD) in Spain. In a cross-sectional study, 638 PREDIMED participants (62% women, mean age 67 y) well phenotyped for cardiovascular risk factors were assessed for food intake and EC using validated questionnaires. Overall, 45.6% were eating-competent. EC was associated with being male and energy intake (P < 0.01). After gender and energy adjustment, participants with EC compared with those without showed higher fruit intake and greater adherence to the Mediterranean diet (P < 0.05) and tended to consume more fish (P = 0.076) and fewer dairy products (P = 0.054). EC participants tended to have a lower BMI (P = 0.057) and had a lower fasting blood glucose concentration and serum LDL-:HDL-cholesterol ratio (P < 0.05) and a higher HDL-cholesterol concentration (P = 0.025) after gender adjustment. EC participants had lower odds ratios (OR) of having a blood glucose concentration >5.6 mmol/L (0.71; 95% CI 0.51-0.98) and HDL-cholesterol <1.0 mmol/L (0.70; 95% CI 0.68-1.00). The OR of actively smoking, being obese, or having a serum LDL-cholesterol concentration > or =3.4 mmol/L were <1.0, but the 95% CI included the 1.0 (P > 0.1). Our findings support further examination of EC as a strategy for enhancing diet quality and CVD prevention.

Small amounts of phytosterols in natural foods appear to be bioactive in cholesterol lowering.

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