Concord grape juice is as beloved for its lip-smacking taste as it is respected for its beneficial antioxidants. Recently researchers found another reason to praise the beverage: the polyphenols in Concord grape juice may play an important role in the support of blood pressure control and healthy brain function. They presented their findings at the 4th International Conference on Polyphenols and Health (ICPH), an event sponsored by Welch Food Inc., makers of Welch’s brand Concord grape juice products.
Dr. Joseph Vita of Boston University School of Medicine presented data from a study that compared the effect of Concord grape juice on blood pressure, fasting blood glucose and insulin levels to the effects of a calorie-matched, non-polyphenol-containing, placebo beverage. His study included 64 men and women with blood pressures classified as pre-hypertension or stage 1 hypertension. None of the study participants were on any medication for their elevated blood pressure.
The study was based on the premise that nocturnal blood pressure (blood pressure at night) reflects cardiovascular health: under healthy circumstances, blood pressure will dip down at night (“nocturnal dipping”). Evidence suggests that “non-dippers” have increased risk for future cardiovascular events.
While this research did not find a significant decrease in blood pressure using 24-hour ambulatory blood pressure monitoring, other results suggested that the consumption of Concord grape juice may have a beneficial impact on blood pressure control. This study showed that drinking Concord grape juice had favorable effects on nocturnal blood pressure, while body weight, blood glucose and fasting insulin levels were not impacted. The placebo had the opposite effect, with a rise both in nocturnal blood pressure and fasting glucose.
In another study presented at ICPH (and subsequently published in the British Journal of Nutrition (2010), 103, 730–734), Robert Krikorian, PhD, of the Department of Psychiatry and Behavioral Neuroscience at the University of Cincinnati Academic Health Center in Cincinnati, OH, and his colleagues set out to examine the effect of the various flavonoids, antioxidants and phenolic compounds in Concord grape juice and their effect on age-related cognitive decline.
“There is a relatively large body of basic research showing cognitive benefit in older animals when supplemented with berry fruits,” explained Dr. Krikorian. “Recently, a study involving Concord grape juice specifically indicated such benefit. Also, there have been several positive human trials with Concord grape juice in individuals with cardiovascular disease. Given the pre-clinical research and the fact that factors involved in general health also are pertinent to brain health, we felt a human trial with memory outcomes was reasonable.”
During the study, 12 older adults with early memory loss each drank 100% Concord grape juice or a calorie-matched placebo for 12 weeks and were tested with measures of memory function, including both verbal and non-verbal tasks. “While there were no differences between the groups at baseline, following treatment, those drinking Concord grape juice demonstrated significant improvement in list learning. In addition, trends suggested improved short-term retention and spatial (nonverbal) memory,” said Dr. Krikorian. “These results with Concord grape juice are very encouraging and certainly warrant additional study. A simple, easy-to-incorporate dietary intervention that could improve or protect memory function, such as drinking Concord grape juice, may be beneficial for the aging population.”
“Previous research supports Concord grape juice’s role in promoting heart-healthy flexible arteries, which can contribute to healthy circulation. To add to that, studies indicate that a diet rich in antioxidants, such as those found in colorful fruits, vegetables and their juices, may help slow and possibly even reverse age-related cognitive decline,” said Casey Lewis, nutritionist and H&N marketing lead at Welch Foods Inc. “Dr. Krikorian’s research builds on previous work in this area to support the notion that what’s good for your heart may also be good for the mind. While Dr. Krikorian's work was a pilot study including a small number of participants, and additional research is certainly necessary, these research findings suggest that Concord grape juice may positively impact memory in older adults and thus may be beneficial for the growing aging population.
“Our findings are exciting because they represent the first demonstration of benefit in the older adult population,” adding that Welch Foods has funded a second study that is already underway. “In the second study we have extended the intervention from 12 to 16 weeks and some of the subjects will [undergo] brain imaging to see if we can observe changes in brain activation in response to the intervention.”
Welch’s hopes to use the findings from both studies to help educate its consumers about the benefits of Concord grape juice. “Welch’s has well over a decade of nutrition and grape research and we continue to partner with leading researchers and invest in this science to give us a deep understanding of the true goodness and health benefits associated with the Concord and Niagara grape and their respective juices,” Ms. Lewis said. “We use learnings from this research to guide the creation of products that meet families’ health and nutrition needs and to educate both consumers and health professionals on the importance of consuming a healthful diet, including fruits, vegetables and their juices.”