One cup of blueberries daily reduces BP

Just a cup of blueberries every day could help reduce blood pressure and arterial stiffness, both of which are associated with heart disease.

"Our findings suggest that regular consumption of blueberries could potentially delay the progression of prehypertension to hypertension, therefore reducing cardiovascular disease risk," said Sarah Johnson from Florida State University.

Over an eight-week period, 48 post menopausal women were randomly assigned to receive either 22 grams of freeze-dried blueberry powder -- the equivalent to one cup of fresh blueberries -- or 22 grams of a placebo powder.

Participants receiving the blueberry powder on average had a five percent decrease in systolic blood pressure, which is the top number in the blood pressure reading.

They also saw a 6.3 percent reduction in diastolic blood pressure, or the bottom number measuring the pressure in the arteries between heartbeats.

Additionally, participants in the blueberry-treated group had an average reduction of 6.5 percent in arterial stiffness.

They also found that nitric oxide, a blood biomarker known to be involved in the widening of blood vessels, increased by 68.5 percent.

This rise in nitric oxide helps explain the reductions in blood pressure.

"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," Johnson said.

The study appeared in the Journal of the Academy of Nutrition and Dietetics.