Walnuts have been extensively studied for their cardiovascular benefits, especially their role in supporting arterial health. Multiple clinical trials and meta-analyses indicate that regular walnut consumption can improve endothelial function, reduce LDL cholesterol, and decrease markers of inflammation, all of which are important for arterial health. Walnuts are rich in polyunsaturated fatty acids (particularly alpha-linolenic acid, an omega-3 fatty acid), antioxidants, and phytochemicals, which collectively help reduce oxidative stress and improve vascular function.

For example, a 2019 systematic review and meta-analysis published in the journal Nutrients found that walnut-enriched diets led to significant reductions in total and LDL cholesterol, two key risk factors for atherosclerosis. Other studies, such as those published in Circulation and American Journal of Clinical Nutrition, have shown that short-term walnut supplementation can improve endothelial function, a measure of artery health. The positive effects are thought to be due to improvements in lipid profiles, reductions in inflammation, and enhanced antioxidant status.

While most of the evidence comes from dietary intervention studies rather than studies using walnut extracts or supplements, the consensus in scientific literature is that walnut consumption can meaningfully benefit arterial health, especially as part of an overall healthy diet.