The Scientific Evidence for a Beneficial Health Relationship Between Walnuts and Coronary Heart Dise
The full report can be viewed by clicking on the link above. This blog cuts to the chase and presents the conclusion.
CONCLUSIONS
Walnuts, as part of a heart-healthy diet, lower blood cholesterol concentrations in humans and animals.
Walnuts are unique compared to other nuts because they are predominant in n-6 (linoleate) and n-3 (linolenate) polyunsaturated fatty acids rather than the monounsaturated fatty acids that are present in most other nuts. Walnuts, as do other nuts, have a high fat content, but are low in saturated fatty acids. These fats are similar to liquid vegetable oils and margarines made from liquid vegetable oils.
Walnuts as a food contain multiple health-beneficial components, viz., having a low lysine:arginine ratio and high levels of vitamin E, arginine, folate, fiber, tannins, and polyphenols.
Walnuts have a long dietary history and continue to be readily acceptable as part of the daily diet. The clinical dietary intervention studies show that consuming walnuts does not cause a net gain in body weight when they are eaten as a replacement food.
The supporting human clinical walnut intervention studies suggest reduced relative risk of coronary heart disease, yet they are inconclusive because there have been only five controlled, peer-reviewed, published trials with few subjects. There are few trials of extended duration essential for critical evaluation of the sustainability of the health-beneficial outcomes and evidence of adverse effects (eg, body weight gain and gastrointestinal intolerance). The subjects, though, were representative of the 51% of the adult population in the United States at higher risk of coronary heart disease. The existing studies, considered in their totality, suggest that walnuts, as part of a heart-healthy diet, lower blood cholesterol concentrations. This strong trend needs to be substantiated.
The several large human prospective observational studies, along with their respective subpopulation cohorts, all demonstrated a dose response-related inverse association of the relative risk of coronary heart disease and coronary vascular disease with the frequent daily consumption of small amounts of nuts, including walnuts. This same response outcome is upheld in different population groups (males, females, African-American, the oldest-old and patients with coronary heart disease) for all-cause mortality, with a 30–50% decreased relative risk of coronary heart disease reported.