In the baking supplies aisle at the ShopRite supermarket on Pershing Drive, a one-pound can of shelled walnuts sells for roughly $5.
“They sell mostly during the year-end holidays,” said Lee Morra, the store’s front end manager.
That’s too bad, because walnuts have been shown in a study to improve cardiovascular health in people with Type 2 diabetes.
Eating two ounces of walnuts per day — that’s roughly 14 whole walnuts — in conjunction with a normal diet, is good for you, according to the study by the Yale-Griffin Prevention Research Center.
“We were very gratified by these findings,” said Dr. David Katz, the principal investigator, who is an adjunct Associate Professor of Public Health at the Yale University School of Public Health.
Dr. Katz directs the Yale-Griffin Prevention Research Center.
Walnuts are a rich source of protein, polyunsaturated fats, vitamins, minerals, fiber, antioxidants, and omega‑3 fatty acids.
They would be nutritious for nearly anyone, but in this study a total of 24 adults with type 2 diabetes were instructed to eat two ounces of walnuts each day, along with their normal diets, for eight weeks.
Then they simply followed their normal diets, without the walnuts, for another eight weeks. There was also an eight week washout period between samplings.
The researchers compared the effects of the adults’ usual diets and walnut-enriched diets on their blood vessels’ ability to dilate and increase flow, which is a powerful predictor of overall cardiovascular risk.
They found the blood vessel function improved significantly when people ate the walnuts.
“We all know the adage about an apple a day, but in fact there are other foods that people should consider adding to their daily diets for specific health benefits. Walnuts rank high on that list,” Dr. Katz said.
Diabetes research is important because there are tens of millions of diabetics in the U.S. today, and unfortunately, that number is expected to escalate for the foreseeable future.
So identifying simple, accessible, and even enjoyable lifestyle practices that can help someone with diabetes is vital, Dr. Katz said.
One of the few concerns about eating walnuts is that someone may eat too many of them. A two ounce serving is about 350 calories.
“Yes, too much of any good thing can be a problem. In the case of walnuts, the main issue would be the calories, and the possibility that a high intake of nuts might contribute to weight gain,” Katz said.
Walnuts have also been characterized in popular wisdom as constipating, but that is not true, Katz said. “They are not generally a problem in terms of gastrointestinal function for most people,” he said.
The study was conducted with funding primarily from the California Walnut Commission, with supportive funding from the Centers for Disease Control and Prevention.
It is the latest of a long series of studies performed at the Yale-Griffin Prevention Research Center.
Dr. Katz established the center in 1998 with funding from the Centers for Disease Control.
As director of this research center dedicated to prevention of chronic disease, Katz has acquired and managed more than $20 million in research funds.
Walnuts have a long history. They have been part of the human diet since at least the Stone Age, according to the Web site vegparadise.com.
They are known for a very tough shell and people have joked for centuries about how difficult it is to crack them open. Many American walnuts come from California, where Spanish Franciscan monks established cultivation in the early 1800s.
Eating walnuts is typically done at dessert or snack time. Recipes for cakes and pastries that call for walnuts abound in baking books.
There is also folklore surrounding walnuts The Romans associated the walnut with Juno, the Roman goddess of women and marriage. This led to the practice of women who wanted to become pregnant carrying walnuts in their pockets.
But the Yale Griffin study is concerned only with scientific aspects of walnuts.
The blood vessel function was measured with ultrasound images of the brachial artery in the arm. It was painless. The team also assessed blood lipid levels, and blood glucose control.
For more information on Griffin Hospital go to griffinhealth.org.
