We read with great interest the article by Fraser and colleagues1 regarding a putative protective effect of nut consumption against the risk of coronary heart disease. These investigators obtained extensive dietary information from over 30 000 individuals; these data were related to the risk of morbidity and mortality from coronary artery disease. They found that frequent consumption of nuts reduced the risk of experiencing fatal or nonfatal myocardial infarctions by 50%. The mechanism of this protective effect is a matter of speculation. The investigators proposed that the favorable polyunsaturated to saturated fat ratio may be responsible for the protective effect. They also noted that nuts are enriched with vitamin E, and that this antioxidant may interfere with the process of atherogenesis.
Nuts and legumes are also enriched in arginine.2 This basic amino acid is the precursor of endothelium-derived relaxing factor, now known to be nitric oxide (NO).3-5