A study appearing in ACS’ Journal of Agricultural and Food Chemistry, found that that although there are over 600 species of blueberries and blueberry-like fruits growing in Mexico, Central and South America, two types of neotropical blueberries were extreme super fruits — they had significantly more antioxidants than a type of blueberry commonly sold in U.S. supermarkets stores. The researchers say that these neotropical blueberries “have the potential to be even more highly promising edible fruits.”
The Florida State researchers recruited 48 women to participate in their eight-week, randomized, double-blind, placebo-controlled clinical trial.
Participants were randomly assigned to receive either 22 grams per day of freeze-dried blueberry powder or 22 grams of a control powder for eight weeks. This dose was equivalent to one cup of fresh blueberries.
The data showed that the blueberry powder was associated with significant reductions in systolic and diastolic blood pressure.
“The changes in blood pressure noted in this study are of clinical significance as they demonstrate that blood pressure can be favorably altered by the addition of a single dietary component (e.g. blueberries),” said lead author Sarah Johnson, PhD.
In addition, improvements in brachial-ankle pulse wave velocity were also reported. Pulse wave velocity is a non-invasive method for assessing arterial stiffness and has been shown to predict future cardiovascular events.
In the current study, brachial ankle pulse wave velocity (baPWV), which is a composite measure of central (aortic) and peripheral arterial stiffness, was significantly reduced after eight weeks in the blueberry-treated group, whereas there were no changes in the control group.
On the other hand, carotid-femoral pulse wave velocity (cfPWV), the best measure of aortic stiffness, did not change in either group. This suggests that peripheral arteries may be more responsive to dietary interventions than central arteries.
“This [study] suggests that regular consumption of blueberries over the long term could potentially delay the progression of hypertension and reduce cardiovascular risk in postmenopausal women,” concluded the researchers.