If you’ve resolved to improve your diet in 2014, there’s one small step you can take that will reap big rewards, according to new research from the Yale-Griffin Prevention Research Center: incorporating walnuts into your diet.
Previous studies have established the health benefits of nuts, including lowering cholesterol levels, facilitating weight loss, decreasing the risk of heart disease, and boosting brain health.
To determine the effect of walnuts on cardiovascular health in overweight adults, the researchers looked at 46 nonsmokers ages 30–75 who had a body-mass index (BMI) greater than 25 (BMI is a measure of weight relative to height; a value of 25–29.9 is considered overweight), a waist circumference greater than 40 inches for men and 35 inches for women, and one or more additional risk factors for the metabolic syndrome (a precursor of cardiovascular disease and diabetes).
The participants were randomly assigned to either follow their regular diet plus walnuts or their regular diet without walnuts for eight weeks, followed by a four-week break. At the end of the break, the volunteers were switched to the other group for another eight weeks. Those assigned to the walnut group were instructed to consume 56 grams (approximately a half-cup) of shelled, unroasted English walnuts each day either as a snack or as part of a meal.
The investigators found that the addition of walnuts to the diet improved the endothelial function of the blood vessels — a measure of how well vessels are able to open and increase blood flow, and a predictor of cardiovascular risk — and it did not lead to weight gain in the study participants.
“We know that improving diets tends to be hard, but adding a single food is easy. Our theory is that if a highly nutritious, satiating food like walnuts is added to the diet, there are dual benefits: the benefits of that nutrient rich addition and removal of the less nutritious foods,” noted lead study author David Katz, MD, MPH.
The study authors recommend further research on the topic.
For more information, read the article “Walnuts in Diet Can Improve Endothelial Functions for Overweight Adults” or see the study in the Journal of the American College of Nutrition. And to incorporate walnuts into your diet, try one of the following recipes: