On average, one ounce of nuts provides about 4 grams of protein, 2-3 grams of dietary fiber, between 160 and 200 calories, and about 13 to 20 grams of fat. Most nuts are rich in monounsaturated fat, and this lowers serum LDL and total cholesterol levels, without lowering the good HDL cholesterol levels. See Table 1 for the fat content of some common nuts. Furthermore, an ounce of nuts typically contains 2-5 grams of polyunsaturated fat. The polyunsaturated fat in the nuts will also lower blood lipid levels.
Nuts also contain a number of important vitamins and minerals.
In addition, most nuts have substantial amounts of zinc, copper, and protective phytochemicals such as ellagic acid and flavonoids. The tocopherols are a form of vitamin E known to prevent unwanted oxidation of LDL cholesterol. The protective effect of nuts was seen after adjustment for many known risk factors for heart disease. The Women's Health Study in Iowa also found an association between nut consumption and decreased risk of heart disease. The Heart Study from the University of Nevada, Reno found that frequent consumers of nuts tend to have lower body weights and are more health conscious than those not eating nuts.