Blueberries
may help reduce blood pressure and arterial stiffness
Florida State University
Just one cup of blueberries per day could be the key to reducing
blood pressure and arterial stiffness, both of which are associated with
cardiovascular 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
A. Johnson, assistant director of the Center for Advancing Exercise and
Nutrition Research on Aging (CAENRA) and postdoctoral fellow in the Department
of Nutrition, Food and Exercise Sciences at Florida State University.
Johnson and a team of FSU nutrition and exercise scientists are
the authors of a new paper, "Daily blueberry consumption improves blood
pressure and arterial stiffness in postmenopausal women with pre- and stage
1-hypertension." Their work is found in the Journal of the Academy
of Nutrition and Dietetics.
"Cardiovascular disease is the leading cause of death in
the United States," she said. "Once women go through menopause, this
puts them at an even greater risk for it. 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."
Over an eight-week period, 48 postmenopausal women with pre- and
stage-1 hypertension 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, meanwhile, continued their
normal diet and exercise routines.
At the beginning of the study, the team took participants' blood
pressure and measured their arterial stiffness and select blood biomarkers.
At the end of the eight weeks, participants receiving the
blueberry powder on average had a 7 mmHg (5.1 percent) decrease in systolic
blood pressure, which is the top number in the blood pressure reading that
measures the pressure in the arteries when the heart beats. They also saw a 5
mmHg (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 97 cm/second (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. That is
important, Johnson said, because arterial stiffness and the narrowing of blood
vessels are both a part of hypertension. This rise in nitric oxide helps
explain the reductions in blood pressure.
Previous studies on blueberries have shown positive effects on
cardiovascular risk factors including blood pressure, but they all included
large amounts of blueberry powder consumption, anywhere from 50 grams to 250
grams. In the case of 250 grams, that would translate to more than 11 cups of
fresh blueberries, which may not be realistic for people to consume on a
regular basis.
Johnson said that future studies will consider other dosages of
blueberries, longer intervention periods and other sample populations.
Johnson is joined on the paper by Department of Nutrition, Food
and Exercise Sciences professors Bahram H. Arjmandi and Arturo Figueroa; Campus
Recreation Wellness Coordinator Lauren T. Ormsbee; Oklahoma State University
Department of Statistics Department Head and Professor Mark E. Payton; and San
Diego State University School of Exercise and Nutritional Sciences Professor
Shirin Hooshmand. Florida State University graduate students Negin Navaei,
Alexei Wong, Roy Kalfon, Rafaela G. Feresin and Marcus L. Elam also
contributed.
The research was funded by the U.S. Highbush Blueberry Council
(USHBC).
Story Source:
The above story is based on materials provided by Florida State University. Note: Materials may be edited for content and
length.
Journal Reference:
Sarah A. Johnson, Arturo Figueroa, Negin Navaei, Alexei Wong,
Roy Kalfon, Lauren T. Ormsbee, Rafaela G. Feresin, Marcus L. Elam, Shirin
Hooshmand, Mark E. Payton, Bahram H. Arjmandi. Daily Blueberry Consumption
Improves Blood Pressure and Arterial Stiffness in Postmenopausal Women with
Pre- and Stage 1-Hypertension: A Randomized, Double-Blind, Placebo-Controlled
Clinical Trial. Journal of the Academy of Nutrition and Dietetics,
2015; DOI:10.1016/j.jand.2014.11.001
Cite This Page:
Florida State University. "Blueberries may help reduce
blood pressure and arterial stiffness." Science Daily,
8 January 2015. <www.sciencedaily.com/releases/2015/01/150108113525.htm>.