A new study just released in the American Journal of Clinical Nutrition found that different flavors of peanuts—salted, spicy, honey-roasted, or unsalted—result in positive health benefits. The study, "A Randomized Trial on the Effects of Flavorings on the Health Benefits of Daily Peanut Consumption," was conducted at Purdue University and included over 150 men and women who incorporated peanuts into their daily diet for 12 weeks.
"Regardless of flavoring, peanut consumption offered significant benefits to participants with elevated serum lipids and blood pressure," says Dr. Richard Mattes, professor of nutrition science at Purdue University. Results showed that all varieties of peanuts significantly decreased mean diastolic blood pressure in all participants. For those who had high blood pressure, the changes were greatest over the first two weeks of the study, and were sustained throughout the 12 weeks. Interestingly, the findings were similar for salted and unsalted peanuts. While all participants decreased their blood pressure, those who ate salted or unsalted peanuts had slightly greater decreases than those who consumed spicy or honey-roasted peanuts.
The paper explains that these results may be due to the arginine found in peanuts, "which promotes the production of nitric oxide—a vasodilator that potentially leads to a decrease in blood pressure." USDA data show that peanuts contain more arginine than any other whole food, including other nuts.
In addition, as shown in previous research, this study found that daily peanut intake reduced total serum cholesterol and triglyceride levels in participants who had high levels at the start. High blood pressure is the number one risk factor for cardiovascular disease, while high blood cholesterol continues to be a major risk factor as well.
Participants were randomly assigned three 0.5-ounce portions of three peanut flavors or just 1.5 ounces of one flavor, which were eaten as a snack or as part of a meal. Researchers took blood samples every four weeks and other health measurements every two weeks.
This study was supported by a grant from the U.S. Agency for International Development Peanut Collaborative Research Support Program Prime Award.
Ounce for ounce, peanuts are the most nutrient-dense nut and contain more protein and arginine than any other nut. They consist of eight essential nutrients, are an excellent source of niacin and manganese, and are a good source of fiber, vitamin E, magnesium, folate, copper and phosphorus. Peanuts also have potassium, phytosterols, resveratrol and healthy fats, all of which may benefit health and may help prevent cardiovascular disease.