Alexandria, VA — Eating peanuts every day reduces blood pressure and cholesterol, regardless of whether they’re salted or flavored, according to a Purdue University study.
In the 12-week study, 151 men and women ate three 0.5 ounce servings daily of three flavors of peanuts or 1.5 ounces of one variety every day. Their blood pressure, heart rate and BMI were measured every two weeks and cardiovascular disease risk factors — insulin, cortisol, glucose and lipids — were measured monthly.
At the end of the study, participants who had a higher risk of cardiovascular disease had significantly higher mean reductions in cholesterol, triglycerides and diastolic blood pressure than those with lower risk, although they also had significantly lower blood pressure. Among those with high blood pressure, the changes were greatest in the first two weeks and remained steady throughout the study.
The group who ate salted or unsalted peanuts had slightly greater decreases in blood pressure than those who ate flavored varieties. In addition, whether peanuts were plain or salted had no effect on the results.
However, those who ate multiple flavors of peanuts gained more weight than participants who ate just one type, although increases in the fat-to-lean ratio weren’t significant.
Senior author Richard D. Mattes, PhD, MPH writes: “Regardless of flavoring, peanut consumption offered significant benefits to participants with elevated serum lipids and blood pressure.” His team postulates the arginine content of peanuts increases production of nitric oxide, a vasodilator that can lower blood pressure.
The study, published in the March issue of the American Journal of Clinical Nutrition, was funded by a grant from the U.S. Agency for International Development Peanut Collaborative Research Support Program Prime Award and Purdue University.