Eating blueberries, as part of a healthy diet, may help ward off several key risk factors for cardiovascular disease and diabetes, such as an accumulation of belly fat, high cholesterol, and high blood sugar, according to research reported Sunday at the Experimental Biology conference in New Orleans.
The health benefits of blueberries are thought to be due to their high levels of phytochemicals - naturally occurring antioxidants called anthocyanins found in darkly pigmented fruits and vegetables.
"In the long-term Women's Health Study, it was shown that women who had diets high in anthocyanins had a significantly reduced risk for heart disease," University of Michigan research scientist E. Mitchell Seymour told Reuters Health.
In studies involving overweight rats, Seymour and colleagues looked at the effects of adding freeze-dried blueberry powder to a low-fat and a high-fat diet.
"We looked at things that are relevant to heart disease," Seymour explained, "like total body fat, abdominal fat, blood lipids (fats), and the body's ability to manage blood sugar levels and we found that they were affected by the blueberry."
After 90 days, rats fed the blueberry powder had less abdominal fat and lower levels of cholesterol and harmful triglycerides than control rats that weren't fed any blueberry powder.
Blueberry-fed rats also had improvements in blood sugar levels and in how their bodies used insulin to process sugar for energy - both of which could help keep diabetes at bay.
The benefits of a blueberry-rich diet were more pronounced when combined with the low-fat diet, as compared to the high fat diet, "but the majority of those benefits were still present even in a higher-fat, more typical American diet," Seymour said.
The study was supported by the U.S. Highbush Blueberry Council.