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With a health claim telling us that peanuts can help improve cholesterol levels, and the news on how peanuts reduce the risk of heart disease (the leading cause of death in the United States), the benefits that peanuts bring to other types of disease may be somewhat overshadowed. Did you know, however, that peanuts not only help your heart? The myriad of healthy components that peanuts possess appears to work in multiple ways to improve our health.
One third of people have high blood pressure in the United States, and may not even know that they have it. Having high blood pressure increases your risk of heart disease and stroke. Scientists have learned that the dietary choices we make can have an impact on blood pressure (Appel, 1997). The Dietary Approaches to Stop Hypertension (DASH) eating plan was developed as a dietary pattern that combines nutrients occurring together in food that are thought to be effective at reducing blood pressure. People sticking to the diet substantially lower their blood pressure.
Nuts, seeds, and beans, including peanuts and peanut butter are eaten four to five times per week in the DASH eating plan. Peanuts and peanut butter contain magnesium, potassium, fiber, arginine, and many bioactive components, each of which could be contributing to lowering blood pressure.
The OMNIHeart (Optimal Macronutrient Intake Trial for Heart Health) study took the DASH diet a step further (Appel, 2005). It followed the same diet principles, but tested optimal diet patterns by replacing saturated fat with three different macronutrients:
- Healthy carbohydrates
- Healthy unsaturated fats
- Protein (half from plant sources)
Peanuts and peanut butter were used in all of the diets, but they contributed most to the diet higher in plant protein (about 4 ounces per week). Because all of the diets were healthy, they reduced the risk of heart disease and blood pressure, but the protein diet and the unsaturated fat diets reduced the risk even further. Peanuts contributed healthy plant protein and healthy unsaturated fats to these diets in addition to micronutrients and bioactives. When part of a healthy diet, peanuts, peanut butter, and peanut oil, which is high in unsaturated fats, can help you keep this silent condition in check!
In a 2012 study published in the American Journal of Clinical Nutrition, researchers found that people who consume foods rich in magnesium have fewer strokes. An intake of 100 mg of magnesium per day, which can be consumed in just 2 ounces of peanuts, was associated with a 9% decrease of ischemic stroke. Compared to other nuts, those who consume peanuts and peanut butter achieve higher Recommended Daily Allowances (RDA’s) for many hard to get nutrients, including magnesium.
Peanuts don’t just have one nutrient that can help in preventing cancer; they have many! Unsaturated fats, certain vitamins and minerals, and too many bioactives to mention that have had cancer-preventative effects are all packaged into a peanut kernel (Gonzalez, 2006).
There are many different types of cancer that target different parts of the body, but components in peanuts may act individually or synergistically and by various mechanisms to prevent the progression of this complex disease.
Phytosterols are compounds in peanuts that have been studied in regards to cancer (Woyengo, 2009). They are also known to reduce bad cholesterol, but new evidence is showing that they may inhibit lung, stomach, ovarian, prostate, colon, and breast cancer. Phytosterols may inhibit the growth of cancer cells, their invasion into other parts of the body, and may cut off the blood flow to cancers. One of the main phytosterols in peanuts is called beta-sitosterol.
Researchers at the State University of New York at Buffalo found that phytosterols reduce prostate tumor growth by over 40 percent and cut the occurrence of cancer spreading to other parts of the body by almost 50 percent (Awad, 2000; 2001).
Resveratrol is another compound found in peanuts that has anti-cancer properties. Like phytosterols, resveratrol has also been shown to cut off the blood supply to growing cancers and to inhibit cancer cell growth (Athar, 2006). With a number of bioactives helping to prevent disease and promote health, peanuts can help pack a punch to cancer!
Gallstone Disease occurs when there is too much cholesterol or bilirubin in your bile or when your gallbladder doesn't empty correctly. There are different thoughts as to why the prevalence of gallbladder disease has increased, and it is probably due to various reasons. One of the risk factors is being overweight or obese, which has increased over the past few decades in the US. Another is having high triglycerides or low good HDL cholesterol.
Little attention has been paid to how the diet affects this disease, but what we eat could very well be having an impact. One study that looked at over 80,000 women from the Nurses’ Health Study found that those who ate peanuts and peanut butter five times a week or more had a reduced risk of gallbladder disease by as much as 25% (Tsai, 2004).
Peanuts are known to have beneficial effects on cholesterol, primarily due to their unsaturated fats. As a complex plant food, however, peanuts contain additional nutrients and bioactive compounds that are also likely to be contributing to this effect. In fact, authors of the study indicate that the reduction in risk of gallbladder disease persists when they looked at data with fat out of the picture. Peanuts are certainly acting to help optimize how our bodies’ work and can improve our health when we eat a small amount daily.
Don’t forget to eat your peanuts! They are a food very high in niacin and are an excellent source of vitamin E -- two nutrients that have been shown to protect against Alzheimer’s disease and age-related cognitive decline.
In almost 4,000 people 65 years or older, niacin from food slowed the rate of cognitive decline (Morris, 2003). In another study, 815 people, 65 years or older without Alzheimer’s disease, were followed for almost four years. Although the consumption of vitamin E from supplements had no effect on the incidence of Alzheimer’s, vitamin E intake from food was protective (Morris, 2002). In those who were in the top fifth of intake, incidence of Alzheimer’s disease was reduced by 70%.
A study from the University of Georgia found that vitamin E levels in peanuts are over 26% higher than what is reported in the US Department of Agriculture Nutrient Database for Standard Reference (Shin, 2009). What this means is that eating an ounce of peanuts will provide 3 mg of vitamin E. This is 20% of the recommended intake for adults and up to 50% for children.
Peanuts have resveratrol too. Another bioactive component recognized as being beneficial in Alzheimer’s disease and other nerve degeneration diseases (Chen, 2005). The myriad of protective components in peanuts is just beginning to be understood. For the time being, using your smarts to consume a small amount of peanuts daily may help minimize the damaging effects that can occur as we age.