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Don’t drink and drive, unless it’s grape juice

Red wine may get all the attention, but grapes (and grape juice) have benefits of their own. This randomized trial tested daily grape juice intake, not just for typical cognitive tests, but also for driving performance

Study under review: Concord grape juice, cognitive function, and driving performance: a 12 wk, placebocontrolled, randomized crossover trial in mothers of preteen children

Introduction

Many of the health benefits of plants are attributed to their phytochemicals, a group of non-essential bioactive compounds generally found in fruits, vegetables, whole grains, nuts, and legumes.

More recently, a 2012 systematic review found that a diet rich in polyphenols, a subclass of phytochemicals which includes anthocyanins, proanthocyanidins, flavonols, flavanones, and a few other flavonoids, is associated with improved cognitive function and reduced neurodegeneration in old age. This topic is discussed in Study Deep Dives #15, Volume 2, in which we analyzed a study that found improved cognitive performance in elderly adults with mild-to-moderate Alzheimer’s disease after daily consumption of sweet cherry juice for 12 weeks.

Unfortunately, the mechanisms through which polyphenols may improve cognitive function are still poorly understood. Nonetheless, various mechanisms have been proposed, including a reduction in neuroinflammation, increased synaptic plasticity, protecting neurons against injury from toxins, and improving cerebral blood flow.

Previous research reported that daily consumption of polyphenol-rich concord grape juice (CGJ) for 12[1] and 16 weeks were associated with improvements in verbal learning and memory in older adults with mild cognitive impairment. Taking these findings a step further, the authors of the current study explored whether consumption of CGJ could result in similar cognitive benefits in a population with impaired cognition as a result of chronic stress.

Recent research has shown that consumption of polyphenols from plant-based foods may be able to improve cognitive function. Concord grape juice (CGJ), specifically, has been shown to improve verbal learning and memory in elderly adults with mild cognitive impairment. The current study sought to extend past findings by analyzing the effect of CGJ consumption for 12 weeks on the cognitive performance of middle-aged adults with stressful lifestyles.

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