Women who drank grape juice daily had significantly better immediate spatial memory and driving performance compared to the placebo group
Potent polyphenols found in grape juice have been shown to enhance brain health. According to research presented at the 2015 International Conference on Polyphenols & Health, grape juice enhanced memory function and performance in a group of working mothers.
This study featured 25 healthy working women age 40 to 50 who had pre-teen children. The women were randomly assigned to drink 355mL of grape juice or a placebo daily for 12 weeks. Cognitive function was assessed via a series of challenges including a 25-minute driving simulator test.
The women who drank grape juice daily had significantly better immediate spatial memory and driving performance compared to the placebo group. The researchers also found that the improved cognitive performance remained even after the women stopped drinking the grape juice.
These results are consistent with previous studies. In 2012, researchers found that grape juice boosted memory and mental function in older people who were experiencing mild declines.
Of course, the concern with drinking grape juice is the high percentage of sugar in the juice. Interestingly, at this same conference, researchers from Purdue University presented their research regarding glycaemic response. They found that participants had a lower blood sugar increase after drinking grape juice compared with participants who drank a non-grape sweetened drink.
They concluded that the polyphenols in grape juice may actually help slow down the absorption of the sugars. More research in this area is needed.
The most active polyphenol found in grapes, grape juice and red wine is resveratrol. A 2014 study featured in the Journal of Neuroscience demonstrated that resveratrol supplementation improved memory performance and hippocampal functional connectivity in healthy older adults. Supplementation with resveratrol is a potential alternative for clinicians concerned about the sugar content in grape juice.