Hyperlipidemia, particularly in the form of elevated low-density lipoprotein (LDL) levels, is a major risk factor for coronary heart disease (3). A diet low in saturated fatty acids (SFAs) and higher in monounsaturated and polyunsaturated fatty acids (MUFAs and PUFAs) has been shown to exert beneficial effects on serum lipid profiles. Walnuts are particularly rich in PUFAs such as linoleic acid and α-linolenic acid and thus may help improve serum lipid levels. Recent studies have been conducted to examine effects of walnut consumption on serum lipids in normocholesterolemic and in hyperlipidemic people. Studies of both groups reveal that walnuts tend to improve serum lipid profiles by reducing LDL and total cholesterol levels (5-11). The studies conclude that walnut consumption may help reduce risk of heart disease. As this is a relatively young field of research, more studies using larger sample sizes and clearer standards for accurately attributing properties to walnuts should be conducted to provide a better understanding of the role of walnuts in potentially lowering one’s risk of heart disease.