Health Benefits of Peanuts

Not only do peanuts contain oleic acid, the healthful fat found in olive oil, but new research shows these tasty legumes are also as rich in antioxidants as many fruits.

While unable to boast an antioxidant content that can compare with the fruits highest in antioxidants, such as pomegranate, roasted peanuts do rival the antioxidant content of blackberries and strawberries, and are far richer in antioxidants than apples, carrots or beets. Research conducted by a team of University of Florida scientists, published in the journal Food Chemistry, shows that peanuts contain high concentrations of antioxidant polyphenols, primarily a compound called p-coumaric acid, and that roasting can increase peanuts’ p-coumaric acid levels, boosting their overall antioxidant content by as much as 22%.

Research published in the British Journal of Nutrition (Blomhoff R, Carlsen MH), which identified several nuts among plant foods with the highest total antioxidant content, suggests nut’s high antioxidant content may be key to their cardio-protective benefits.

Nuts’ high antioxidant content helps explain results seen in the Iowa Women’s Health Study in which risk of death from cardiovascular and coronary heart diseases showed strong and consistent reductions with increasing nut/peanut butter consumption. Total death rates decreased 11% and 19% for nut/peanut butter intake once per week and 1-4 times per week, respectively.

Even more impressive were the results of a review study of the evidence linking nuts and lower risk of coronary heart disease, also published in the British Journal of Nutrition. (Kelly JH, Sabate J.) In this study, researchers looked at four large prospective epidemiological studies—the Adventist Health Study, Iowa Women’s Study, Nurses’ Health Study and the Physician’s Health Study. When evidence from all four studies was combined, subjects consuming nuts at least 4 times a week showed a 37% reduced risk of coronary heart disease compared to those who never or seldom ate nuts. Each additional serving of nuts per week was associated with an average 8.3% reduced risk of coronary heart disease.

Practical Tips for lowering risk of heart attack with Peanuts

To lower your risk of cardiovascular and coronary heart disease, enjoy a handful of peanuts or other nuts, or a tablespoon of nut butter, at least 4 times a week.

Resveratrol is a flavonoid first studied in red grapes and red wine, but now also found to be present in peanuts. In animal studies on resveratrol itself (the purified nutrient given in intravenous form, not the food form), this phytonutrient has been determined to improve blood flow in the brain by as much as 30%, thus greatly reducing the risk of stroke, according to the results of a laboratory animal study published in the Journal of Agricultural and Food Chemistry.

Lead researcher Kwok Tung Lu hypothesized that resveratrol exerted this very beneficial effect by stimulating the production and/or release of nitric oxide (NO), a molecule made in the lining of blood vessels (the endothelium) that signals the surrounding muscle to relax, dilating the blood vessel and increasing blood flow. In the animals that received resveratrol, the concentration of nitric oxide (NO) in the affected part of the brain was 25% higher than that seen not only in the ischemia-only group, but even in the control animals.

A number of studies have shown that nutrients found in peanuts, including folic acid, phytosterols, phytic acid (inositol hexaphosphate) and resveratrol, may have anti-cancer effects. A rich source all these nutrients—including the phytosterol beta-sisterol, which has demonstrated anti-cancer actions—peanuts have long been considered a likely candidate as a colon cancer-preventive food.

Colorectal cancer is the second most fatal malignancy in developed countries and the third most frequent cancer worldwide. In Taiwan, not only has incidence of colon cancer increased, but the likelihood of dying from the disease rose 74% from 1993 to 2002.

Taiwanese researchers decided to examine peanuts’ anti-colon cancer potential and conducted a 10-year study involving 12,026 men and 11,917 women to see if eating peanuts might affect risk of colon cancer.

Researchers tracked study participants’ weekly food intake, collecting data on frequently consumed foods and folk dishes such as sweet potato, bean products, peanut products, pickled foods, and foods that contained nitrates or were smoked.

Risk of colon cancer was found to be highly correlated with both peanuts, which greatly lessened risk, and pickled foods, which greatly increased risk, particularly in women.

Eating peanuts just 2 or more times each week was associated with a 58% lowered risk of colon cancer in women and a 27% lowered risk in men.

In women, but not in men, eating pickled foods 2 or more times a week more than doubled the likelihood of developing colon cancer risk for women, increasing their risk 215%.

Practical Tips of lowering Colon Cancer From Peanuts

To help prevent colon cancer, avoid pickled foods, but enjoy peanuts at least twice each week. In addition to that old stand-by, the PB&J sandwich, try some of the following:

• Spread peanut butter on your morning waffle, whole grain toast or mid-morning crackers.
• Add a tablespoon of peanut butter to your morning smoothie.
• Enjoy a handful of dry roasted peanuts with a glass of tomato juice as an afternoon snack.
• Combine peanut butter, coconut milk, and ready-to-use Thai red or green curry paste for a quick, delicious sauce. Pour over healthy sautéed vegetables. Use as a cooking sauce for tofu or salmon.
• Toss cooked brown rice with sesame oil, chopped peanuts, scallions, sweet red pepper, parsley and currants.

When purchasing peanut butter, be sure to read the label. Hydrogenated(trans-) fats and sugar are often added to peanut butter. Buy organic and choose brands that contain peanuts, salt—and nothing else!

Twenty years of dietary data collected on over 80,000 women from the Nurses’ Health Study shows that women who eat least 1 ounce of nuts, peanuts or peanut butter each week have a 25% lower risk of developing gallstones. Since 1 ounce is only 28.6 nuts or about 2 tablespoons of nut butter, preventing gallbladder disease may be as easy as packing one peanut butter and jelly sandwich (be sure to use whole wheat bread for its fiber, vitamins and minerals) for lunch each week, having a handful of peanuts as an afternoon pick me up, or tossing some peanuts on your oatmeal or salad.

Research published in the Journal of Neurology, Neurosurgery and Psychiatry indicates regular consumption of niacin-rich foods like peanuts provides protection against Alzheimer’s disease and age-related cognitive decline.

Researchers from the Chicago Health and Aging Project interviewed over 3,000 Chicago residents aged 65 or older about their diet, then tested their cognitive abilities over the following six years.

Those getting the most niacin from foods (22 mg per day) were 70% less likely to have developed Alzheimer’s disease than those consuming the least (about 13 mg daily), and their rate of age-related cognitive decline was significantly less. One easy way to boost your niacin intake is to snack on a handful of peanuts—just a quarter cup provides about a quarter of the daily recommended intake for niacin (16 mg per day for men and 14 for women).

Although nuts are known to provide a variety of cardio-protective benefits, many avoid them for fear of weight gain. A prospective study published in the journal Obesity shows such fears are groundless. In fact, people who eat nuts at least twice a week are much less likely to gain weight than those who almost never eat nuts.

The 28-month study involving 8,865 adult men and women in Spain, found that participants who ate nuts at least two times per week were 31% less likely to gain weight than were participants who never or almost never ate nuts.

And, among the study participants who gained weight, those who never or almost never ate nuts gained more (an average of 424 g more) than those who ate nuts at least twice weekly.

Study authors concluded, “Frequent nut consumption was associated with a reduced risk of weight gain (5 kg or more). These results support the recommendation of nut consumption as an important component of a cardioprotective diet and also allay fears of possible weight gain.”

Practical Tips: Don’t let concerns about gaining weight prevent you from enjoying the delicious taste and many health benefits of nuts!

• Spread some nut butter on your morning toast or bagel.
• Remember how many great childhood lunches involved a peanut butter and jelly sandwich? Upgrade that lunchbox favorite by spreading organic peanut butter and concord grape jelly on whole wheat bread.
• Fill a celery stick with nut butter for an afternoon pick-me-up.
• Sprinkle a handful of nuts over your morning cereal, lunchtime salad, dinner’s steamed vegetables.
• Or just enjoy a handful of lightly roasted nuts as a healthy snack.