Grape and Blueberry Polyphenols Improve Memory in Elderly

Written by Joyce Smith, BS. A six-month supplementation with a polyphenol-rich extract of blueberry and grape (PEGB), improved verbal episodic memory in healthy older adults.

Our elderly population is increasing significantly in industrialized countries and is expected to peak at two billion by 2050 ¹. Accompanying an increasing aging process is age-related cognitive decline (ARCD) which, although defined as non-pathological, can result in decreased mental function ²  that progresses from midlife (age 35) to 65 years of age and older ³.  Memory loss, the greatest and most serious cognitive concern for the elderly ², calls for strategies that both curtail ARCD and improve quality of life for our aging population and reduce the associated social and economic burden. Previous research has suggested that long-term intake of polyphenols from fruits such as blueberries and grapes may have the ability to support memory and neurological health as we age ⁴.  For example, polyphenols have been shown to increase brain plasticity ⁵, improve learning and working, spatial, and verbal memory ⁶. Polyphenols such as anthocyanins have shown improvements in cognition ⁷ and flavonols have been attributed with reducing cognitive decline ⁸. Thus, the following study sought to evaluate the effect of a 6-month supplementation with a polyphenol-rich grape and blueberry extract on memory in a healthy elderly population.

In a 6-month randomized, double-blind, placebo-controlled trial ⁹, 215 healthy volunteers (age 60-70 years) received 600 mg/day of PEGB, a polyphenol extract of grape (Vitis vinifera L.) and wild blueberry (Vaccinium angustifolium Aiton) or a maltodextrine placebo. In addition to the PEGB supplement, participants provided 3-day food diaries at the beginning and completion of the study.  Measures of cognitive function were assessed at baseline and at 24 weeks of supplementation using the Cambridge Neuropsychological Test Automated Battery (CANTAB) and Paired Associate Learning (PAL), a visuospatial learning and episodic memory test. ¹⁰. Memory evaluation included the VRM free recall and VRMR, a verbal recognition memory test. Working memory was evaluated using the Spatial Span (SPP) and the Reverse SSP tests. In addition, urine samples were tested for PEGB phenolic metabolites to determine a potential association of PEGB supplementation with cognitive decline.

While researchers found no significant effect of PEGB supplementation on paired associate learning among the cohort of participants, PEGB did improve verbal episodic memory, as measured by VRM-free recall. However, a subgroup of older participants with a lower level of education and more advanced cognitive decline, responded favorably to PEGB supplementation and demonstrated a positive association between PEGB supplementation and improvement in episodic memory (VRM-delayed recognition). SPP and Reverse SPP revealed no improvement in working memory in this subgroup. In addition, analysis revealed a lower polyphenol consumption in this group (p for trend = .008.) and a significantly higher excretion of urinary metabolites, indicating an association of increased urinary concentrations of flavonol metabolites with memory improvements.

The present study demonstrated that supplementation with PEGB (Neurophenol®, 600 mg/d) for six months improved episodic memory (the ability to recall previous events and specific details such as people, times and places) in healthy elderly subjects who were already experiencing neurocognitive and memory issues.

Source: Bensalem, Julien, Stéphanie Dudonné, Nicole Etchamendy, Hermine Pellay, Camille Amadieu, David Gaudout, Séverine Dubreuil et al. “Polyphenols from grape and blueberry improve episodic memory in healthy elderly with lower level of memory performance: A bicentric double-blind, randomized, placebo-controlled clinical study.” The Journals of Gerontology: Series A 74, no. 7 (2019): 996-1007.

© The Author(s) 2018. Published by Oxford University Press on behalf of The Gerontological Society of America.

Posted April 21, 2020.

Joyce Smith, BS, is a degreed laboratory technologist. She received her bachelor of arts with a major in Chemistry and a minor in Biology from  the University of Saskatchewan and her internship through the University of Saskatchewan College of Medicine and the Royal University Hospital in Saskatoon, Saskatchewan. She currently resides in Bloomingdale, IL.

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