ORONO, Maine -- New research at the University of Maine is showing that wild blueberries may have a cardioprotective effect by helping to regulate blood pressure and combat heart disease, specifically atherosclerosis.
Maine is the world's largest producer of wild blueberries.
David Bell, executive director of the Maine Wild Blueberry Commission, said Friday that Dr. Dorothy Klimis-Zacas, professor of clinical nutrition and lead researcher from the Department of Food Science and Human Nutrition, conducted the studies over the past decade. They involved feeding different breeds of laboratory rats a whole-fruit diet, rather than puree or juice as in past studies.
The body of research conducted at the university supports the potential protective effect of wild blueberries on cellular signaling within the vascular environment, Bell said. These findings suggest that the consumption of wild blueberries could improve vascular function and decrease the vulnerability of blood vessels to oxidative stress.
Klimis-Zacas' research contributes to a growing body of evidence that wild blueberries, as part of a well-balanced diet, have the potential to reduce chronic disease risk and promote healthy aging, according to Susan Davis, M.S., R.D., nutrition adviser to the Wild Blueberry Association of North America.
"Studies like these make it clear that food truly can be medicine and that healthy eating is critical to a long and healthy life," Davis said. "Something as simple as having 1 cup of fruits and vegetables at every meal will pay large dividends in health. "Our studies confirm our hypothesis that wild blueberry-enriched diets significantly diminish arterial constriction in animal models by relaxing blood vessels, which may have implications on blood pressure regulation in both animal models with normal blood pressure and ones with high blood pressure," Klimis-Zacas said. "We also discovered that wild blueberries operate differently in animal models, but the end result is to aid in maintenance of a functional endothelium which may help prevent vascular complications associated with hypertension." Klimis-Zacas said controlling oxidative stress and inflammatory responses in the vascular environment is key to cardiovascular health. "We continue to focus our research on the role of diet in disease prevention," she added. Davis said that eating a variety of fruits and vegetables is key to good health, but because USDA research findings ranked wild blueberries highest in antioxidant capacity per serving, she recommends eating them every day. The study showed that a serving of wild blueberries had more antioxidant capacity than a serving of cranberries, strawberries, raspberries, apples and even cultivated blueberries. Antioxidants are important in terms of their ability to protect against oxidative cell damage that can lead to conditions such as Alzheimer's disease, cancer and heart disease, as well as conditions linked with chronic inflammation.