Nuts - A “Top 10” Food for Better Health

by Gay Riley, MS, RD, CCN
NetNutritionist.com

To achieve optimal nutritional health and as a functional food to protect the body against disease, nuts are one of the top 10 important foods to add to your diet.

Research has proven the frequent eating of nuts appears to dramatically improve health1.

• Although nuts are high in fat, it is mostly unsaturated which is liquid in the blood. Fats from nuts lower inflammation, lubricate the joints, and stimulate the movement of toxins from the body.
• Studies on almonds and walnuts show that both have a beneficial effect on blood cholesterol levels.
• The protein in nuts is high in arginine, a precursor to nitric oxide, which is needed to help keep blood vessels relaxed and open, and to help prevent clotting, which also may improve blood pressure.
• Walnuts in particular are high in alpha-linolenic acid, an essential (n-3 or omega) fatty acid that is protective to the heart and circulation. This fat has been shown to reduce the risk of heart disease and fatal arrhythmias in various studies. These omega fats may also help in depression.
• Nuts are also good sources of dietary fiber, magnesium, copper, folic acid, vegetable protein, potassium, and vitamin E, all of which have been shown to be important for heart health.

Primarily, nut eating greatly lowers the risk of heart disease2 The Adventist Health Study at Loma Linda University in California revealed those eating nuts daily had up to 60% fewer heart attacks than those who ate nuts less than once per month3. The beneficial effect of nut consumption was found for men, women, vegetarians, meat-eaters, fatter people, thinner people, the old, the young, those who did much exercise and those who did little exercise. 31,000 caucasian Californian Seventh Day Adventists participated, and a similar study found the same benefits of nut eating for African Americans living in California4.

Other large studies have confirmed the benefits to the heart of nut eating2, 5-8. In addition to the cardiac benefits of consuming nuts, the risks of having a stroke9, of developing type 2 diabetes10, of developing dementia11, of advanced macular degeneration12 and of gallstones 13 have all been found to be lowered by eating nuts. Research suggests that daily nut eaters gain an extra five to six years of life free of coronary disease14 and that regular nut eating could increase longevity by about 2 years15.

The more often nuts are eaten the better, as the benefits appear to increase as the frequency of nut consumption increases. The risk of fatal coronary disease and the risk of developing type 2 diabetes both appear to decrease steadily as nut consumption increases from less than once a week to once or more per day10, 16. Raw, natural or roasted nuts are most beneficial to health. Oily, processed nuts or sweetened nuts compromise the nutritional benefits and become rancid quickly. They can also add to the caloric value and alter the nutritional benefit of the food.

Some current evidence suggests a moderate intake of nuts does not seem to cause weight gain1, 17. For example, in the nurses' study the frequent nut consumers were actually a little thinner on average than those who almost never consumed nuts6, and daily supplements of almonds or peanuts for six months resulted in little or no increase in body weight18. Nuts appear to satisfy hunger sufficiently well to appropriately reduce the consumption of other food.

Interestingly though, the cholesterol is lowered by a larger amount than would be expected just from the polyunsaturated and monounsaturated fatty acid composition of nuts19. However, the reason for this is not clear. Nuts, though, are good sources of fiber, vitamin E, folic acid, copper, magnesium and the amino acid arginine, for each of which there is evidence of a role in preventing heart disease19. Nuts are the best dietary source of manganese and contain plant sterols, the compounds now added to some margarines to reduce cholesterol adsorption from food, and are a good source of boron20.

Just what quantity of nuts should be eaten? The studies above suggest that 30 to 60 grams (1-2 oz.) of nuts should be consumed daily to gain the maximum benefits seen. That is about 180-360 calories. An ounce each day is a good goal. Raw or roasted, it doesn't seem to matter. Have them in small quantities on foods and for snacks. Serving size (around 50 calories or ¼ ounce) for natural nuts is 6 almonds, 4 walnut or pecan halves, 10 peanuts, 1 T pumpkin seeds or sunflower seeds, 5 cashews, 5-6 hazelnuts, 3-4 filberts, and 2-3 macadamia nuts. An ounce (30 grams), approximately ½ cup of any of these nuts, ranges from 160-210 calories.

For optimal health, enjoy a variety of nuts and seeds daily: walnuts, hazelnuts, Brazil nuts, filberts, almonds, cashews, peanuts, sunflower seeds, sesame seeds, flax seed, and non-hydrogenated nut butters such as peanut butter, almond butter, and tahini. Most commercial peanut butters have saturated fats (hydrogenated) and high fructose corn syrup added to them to prevent oil separation and for taste, so it is probably healthier to seek out brands made from peanuts (and salt) only. Many health food stores offer grinders so you can grind the peanuts right in the store. Fresh ground peanut butter does not separate easily and spreads well. You can also mix nut butters and add a little natural applesauce for your own personal spread. Add nuts to salads, stir fry, and toppings on desserts.

For the large majority of the population though, an increase in nut consumption would appear to be desirable and "regular nut consumption can be recommended as a replacement for consumption of refined grain products or red or processed meats"10.

Nuts are an important component of Dr. Willett’s Healthy Eating Pyramid 33, and peanut butter was a key component in a successful weight-loss study21. The success of this moderate-fat diet in enabling and maintaining weight loss has stimulated the development of a popular Peanut Butter Diet22 . Almonds were a major part of the vegetarian "Portfolio" diet23, which was just as effective for lowering cholesterol as the drug Lovastatin.

A warning about nut allergies. Some people may be allergic to nuts, most commonly peanuts. If nut allergies are suspected, avoid the suspicious food and have an allergy test to confirm. British24 and American25 surveys suggest that between one in one hundred and one in two hundred people may be allergic to one or more types of nuts. Both children and adults can be affected, and the most common symptoms seem to be skin rashes and hoarseness in the throat26.

REFERENCES

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