Nutz for Nuts

Health in a nutshell

For starters, peanuts and tree nuts, including almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts and pistachios, are packed with vitamin E, calcium, magnesium, potassium and fiber—shortfall nutrients for many Americans. In addition, they contain a variety of phytochemicals, such as phytosterols, carotenoids, flavonoids and proanthocyanidins, which may help protect against chronic diseases.

Eating a variety of nuts yields the maximum benefits, since each nut has its unique nutrient profile. For example, walnuts are an excellent source of alpha-linolenic acid (ALA), an essential omega-3 fatty acid that can help reduce the risk of several diseases. Almonds top the fiber list with approximately 12% fiber. Nuts are also rich in protein, containing 2 to 7 grams per oz., depending on the variety, which makes them a popular protein source among the growing number of vegetarians. The 2005 Dietary Guidelines recommend that vegetarians substitute 1½ oz. of nuts for 5½ oz. of meat, poultry and/or fish.

Best of all, nuts are perfectly aligned with the current model for healthful eating that experts extol—a diet rich in whole plant foods, an eating pattern linked with a decreased risk of a number of chronic diseases, such as coronary heart disease (CHD), certain types of cancer, insulin resistance and high blood pressure.

Nuts take heart

Nuts really took a crack at heart health when FDA approved the first qualified health claim for a food in 2003. The claim states, “Scientific evidence suggests but does not prove that eating 1.5 oz. per day of most nuts (peanuts, almonds, Brazil nuts, cashew nuts, hazelnuts, macadamia nuts, pecans, pine nuts, pistachio nuts and walnuts), as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease.” The evidence presented to FDA included more than 30 studies pertaining to nut consumption and its positive effects on serum lipids and reduction of heart disease risk.

cashew fruit-yep nut is inside!

According to the International Tree Nut Council, Davis, CA, research suggests eating 1½ oz. of nuts per day has the potential to reduce the incidence of CHD in the United States by 30% to 50%. The National Institutes of Health’s Dietary Approaches to Stop Hypertension (DASH) eating plan suggests 1½ oz. of nuts four to five times per week, because they are rich sources of energy, magnesium, potassium, protein and fiber.

All peanuts and tree nuts are good sources of monounsaturated and polyunsaturated fats, which have been shown to lower total and low-density lipoprotein blood cholesterol levels. They also contain a variety of potentially cardio-protective components, such as vitamin E, selenium, magnesium, copper, potassium, beta-sitosterol and omega-3 fatty acids.

Say nuts to cancer

Based on the report, “Food, nutrition and the prevention of cancer: a global perspective,” developed by the American Institute for Cancer Research, Washington, D.C., and the World Cancer Research Fund, London, which drew upon more than 4,500 global research studies, diet and lifestyle can reduce cancer rates by 30% to 40%. One of the report’s key recommendations is to consume a predominantly plant-based diet. These foods contain high amounts of antioxidant phenolics, fibers and many phytochemicals that may protect against cancer. Special attention is being focused on beta-sitosterol, a plant sterol found in nuts that has been shown to inhibit cancer growth and offer protection from colon, prostate and breast cancer.

In Cancer Epidemiology Biomarkers & Prevention (2004, 13:1,595-1,603), researchers investigated the association of nut and seed intake with colorectal cancer risk in a European prospective study that included more than 478,000 subjects. The results showed a significant protective effect of increased nut intake on colon cancer in females. Additional research needs to occur to better understand nuts’ potential cancer-fighting properties.

The skinny on nuts

Caution has been administered liberally along with recommendations for consuming nuts, due to their fat content and caloric density. While nuts contain many health-promoting nutrients, if people gorge and gain weight, then the benefits can quickly vanish. A single ounce of nuts contains 160 to 200 calories and 13 to 22 grams of fat, depending on the variety.

But, some studies show an inverse association between frequency of nut consumption and body weight, possibly because the nutritional profile of nuts seems to offer satiety value that may offset their caloric density. According to a report in the American Journal of Clinical Nutrition (2003, 78(3):647S-650S), data demonstrate that nut consumption among free-living individuals is not associated with higher body-mass index compared with non-nut consumers.

Nuts may also offer advantages for diabetic meal planning, thanks to their low glycemic index. And the antioxidants found in nuts may offer protection against Alzheimer’s disease. The good news about nuts has prompted experts to push the consumer message of eating a handful of nuts per day (about 1 to 1½ oz.). Not a bad exchange—a fistful of tasty nuts for a bounty of health benefits.

Sharon Palmer is a registered dietitian with 16 years of experience in health-care and foodservice management. She writes on food and nutrition for newspapers, magazines, websites and books. Palmer makes her home in Southern California