Study: Walnuts Protect Against Heart Disease, Diabetes

DERBY, Conn.Eating walnuts may help to protect against heart disease, according to a new study published in the Journal of the American College of Nutrition.

The study, conducted by the Yale-Griffin Prevention Research Center in Derby, Conn., examined the health affects of consuming walnuts daily in a group of adults at risk for developing diabetes or heart disease. Researchers examined 46 overweight adults, 28 women and 18 men, who had an average age of 57 years. The participants had at least one of several conditions that increase the risk of cardiovascular disease and diabetes such as high blood pressure, high blood glucose, high triglycerides or low HDL cholesterol as well as an elevated waist circumference. Study participants practiced their usual eating habits for an eight-week period, which served as the control phase. This was followed by another eight-week period, the walnut phase, in which participants continued their usual eating habits, but also consumed two ounces of walnuts per day and adjusted for the extra calories from the walnuts so that their daily calorie intake would be consistent with the control phase. Results revealed that after eight weeks of daily walnut intake, the participants' blood vessel function improved significantly compared to the control phase. Further, they experienced reduction of systolic blood pressure. Participants weight and waist circumference remained stable throughout.

Study results provide evidence that walnuts can play a key role in protecting against heat disease in at-risk individuals. "Our work to date has shown clear benefits of adding walnuts to the diet for people with, and at risk, for diabetes," said David L. Katz, director of the Yale-Griffin Prevention Research Center, and principal investigator of this study. "To some extent, this is because walnuts are concentrated in a variety of health-promoting nutrients, including omega-3 fat. The results are also probably due to the fact that eating more walnuts, which tend to help us feel full and stay full, means eating less of other, less nutritious foods," Katz added. These results are consistent with findings of a prior study that revealed eating walnuts significantly improved blood vessel function in individuals with diabetes.