The news just keeps getting better and better about the health value of walnuts, already linked to lowering your cholesterol and slowing the progress of prostate cancer in mice.

Researchers from Penn State University and the University of Guelph monitored the health of 22 healthy patients with elevated LDL cholesterol levels -- the bad kind that increases your risk of heart disease -- to determine how diets chock full of walnuts and walnut oil can prepare the human body to deal with stress.

Each patient ate three specific diets lasting six weeks apiece. One diet excluded walnuts altogether, while the others included small amounts of walnuts, walnut oil and flaxseed oil (either mixed into prepared foods or offered as snacks). Between each diet, researchers also measured the blood pressure of patients in a pair of stress tests, involving public speaking and dunking one foot in icy cold water.

The healthy effect of walnuts was seen in significant drops of average diastolic blood pressure (the bottom number measuring artery pressure when the heart is resting) among patients eating diets rich in walnut oil and walnuts. And, after giving a smaller group of patients a vascular ultrasound, researchers learned artery dilation was greatly improved and the amount of c-reactive protein in the blood fell when patients consumed flaxseed oil in addition to walnuts and walnut oil.

Penn State Live October 4, 2010