Eating one cup of blueberries daily may lower blood pressure (BP) and decrease arterial stiffness, new data published in the Journal of the Academy of Nutrition and Dietetics indicate.
“Our findings suggest that regular consumption of blueberries could potentially delay the progression of prehypertension to hypertension, therefore reducing cardiovascular disease risk,” study research Sarah A. Johnson, assistant director of the Center for Advancing Exercise and Nutrition Research on Aging and postdoctoral fellow at Florida State University, said in a press release.
In their study, Johnson and colleagues randomly assigned 48 postmenopausal women with prehypertension or stage 1 hypertension to receive 22 g of freeze-dried blueberry powder, equivalent to one cup of fresh blueberries, or 22 g of a placebo powder for 8 weeks. There were no changes in diet or physical activity among participants.
After 8 weeks, participants who consumed the blueberry powder experienced a decrease in systolic BP from 138 mm Hg at baseline to 131 mm Hg (P<.05) as well as a decrease in diastolic BP from 80 mm Hg at baseline to 75 mm Hg (P<.01).
Arterial stiffness as measured by brachial-ankle pulse wave velocity was also reduced in the blueberry powder group, dropping from 1,498 cm/second at baseline to 1,401 cm/second after 8 weeks (P<.01).
The researchers also found greater nitric oxide levels from baseline in the blueberry group, increasing from 9.11 mcmol/L to 15.35 mcmol/L (P<.01) by the study’s conclusion. No change in nitric oxide levels were noted in the control group.
This increase in nitric oxide, which is a biomarker associated with the widening of blood vessels, with regular blueberry consumption may account for the decreases in BP and arterial stiffness seen in that group.
“Cardiovascular disease is the leading cause of death in the United States. Once women go through menopause, this puts them at an even greater risk for it,” Johnson said. “Our findings suggest that the addition of a single food, blueberries, to the diet may mitigate the negative cardiovascular effects that often occur as a result of menopause.”