A diet rich in alpha-linolenic acid from walnuts, walnut oil and flaxseed oil not only lowers bad cholesterol but also decreases markers for blood vessel inflammation in those at risk for cardiovascular disease, according to a Pennsylvania State University study.

While previous studies have shown that walnut supplementation favourably affects cholesterol and other lipids that are signs of cardiovascular risk, this new study is the first to demonstrate that a diet high in walnuts decreases C-reactive protein (CRP), a marker of inflammation strongly associated with heart disease.

"The omega-3 fatty acids in walnuts were converted to the same omega-3 fatty acids found in marine sources, and had a similar effect on inflammation. Reducing inflammation can help decrease the process of arteriosclerosis - the development and build-up of plaque in the arteries," said Dr Penny Kris-Etherton, professor of nutrition at Penn State and primary investigator for the study.

"The important new finding with our research is that a diet high in walnuts beneficially affects multiple risk factors for coronary heart disease, which can have a greater impact on decreasing cardiovascular risk than just targeting single risk factors," Kris-Etherton added.

The research, "Dietary Alpha-Linolenic Acid Reduces Inflammatory and Lipid Cardiovascular Risk Factors in Hypercholesterolemic Men and Women," is published in the November 2004 issue of the Journal of Nutrition.

The study was supported by funding from the California Walnut Commission.