About 58% of walnut weight is fat, and around 81% of the total calories of walnuts are derived from this fat. Walnut fat is qualitatively similar to that of some commonly used oils extracted from grains and seeds.
The favorable fatty acid composition of nuts, that is, a relatively high percentage of polyunsaturated and monounsaturated fatty acids, which may improve blood lipids and other cardiovascular disease risk factors.
The researchers found that both polyunsaturated fatty acid (PUFA)-rich walnuts and monounsaturated fatty acid-zxrich almonds improve the coronary heart disease risk profile by lowering LDL cholesterol.
Walnut can be considered an alternative food source of n-3 fatty acids that does not add cholesterol to the diet due it contains relatively large amounts of the n-3 linolenic acid, about 7 g per 100 g of edible portion, or 12 percent of their total fat content.
Study on Japanese population published in Journal of Nutrition October 2000 shows that the that replacing a portion of the fat in a reference diet with walnuts (43–53 g/d) lowers serum cholesterol concentration by 4% for normal men and 5% for normal women.
Walnuts may reduce risk of heart disease by lowering blood cholesterol
