Wild Blueberry Supplementation Improves Cognitive Performance of Children

by | Jan 28, 2019 | 2016, Brain Health, Flavonoids, Fruits and Vegetables, Infant and Children's Health

Written by Angeline A. De Leon, Staff Writer. Compared to placebo, supplementing with a beverage containing 30 grams of wild blueberry significantly improved performance on a series of cognitive tests examining memory and attention in the participating seven to ten year old school children.

blueberriesStudies looking at the effects of nutrition on brain development have typically focused on the benefits of multivitamin supplementation for cognitive performance in children 1. A growing body of research now shows that flavonoids (a large family of phytonutrients found in fruits and vegetables) also play a key role in supporting cognitive function in animals and humans 2. Berries, in particular, demonstrate an ability to mitigate neuronal stress and enhance pathways associated with brain signaling 3. Previous studies show that supplementation with blueberry anthocyanins can improve visuo-spatial memory 4 and enhance performance on executive function tasks 5. Along with grape anthocyanins, blueberry supplementation has also been found to boost immediate verbal memory within a period of 12 weeks 6. While the mechanism underlying the cognitive-boosting effects of flavonoids is still under study, current evidence suggests that improvement of cerebral blood flow may be involved 7. The majority of research studies examining the role of flavonoids on cognitive function have focused on adults. Therefore, in order to better understand whether the cognitive benefits of anthocyanin-rich blueberries are also applicable to children, a study 8 published in the European Journal of Nutrition (2016) examined the acute effects of wild blueberries (WBB) on the cognitive performance of school-aged children.

A total of 21 children (aged 7-10 years) were enrolled in a double-blind, cross-over study in which they completed three treatment days with a 7-day washout period between treatments. On each day, children were assigned to consume a beverage containing 15 g (equivalent to 240 g fresh wild blueberries, containing 253 mg anthocyanins) or 30 g (equivalent to 120 g fresh wild blueberries, containing 127 mg anthocyanins) of freeze-dried WBB or a placebo drink. On each test day, a low-flavonoid breakfast, snacks, and lunch were provided. At baseline and at 1.15, 3, and 6 hours following treatment on each test day, a cognitive battery (including tests of verbal memory, word recognition, response interference, response inhibition, and levels of processing) was administered.

Composite scores for all the tasks highlighted a significant difference in the children’s cognition results, with the 30 WBB drink providing the best performance and the placebo drink the least effect performance.

Specifically, when compared to placebo, participants in the 30 g WBB treatment group showed significant improvement in final acquisition of a repeated list of words 1.15 h following intervention [significant positive linear trend F(1,20) = 8.76, p = 0.008, with placebo showing greatest negative change (mean = -0.95) and 30 g WBB greatest positive change (mean = 0.57) (p = 0.23)]. While word recognition declined for all doses across sessions, but cognitive effects following acute wild blueberry supplementation old was significantly less for both WBB doses, relative to placebo [decrease in performance for placebo was significantly greater compared to decrease for 15 g WBB (p=0.247) and 30 g WBB ( p = 0.016) Lastly, subjects in the 30 g WBB group showed improved accuracy on the more cognitively demanding trials 3 h following intervention [significant positive linear trend for incongruent condition (p = 0.012) with accuracy lowest for placebo and highest for 30 g WBB at 3 h (p = 0.035)].

Findings from the study suggest that supplementation with anthocyanins is associated with improved cognitive performance, particularly for word acquisition and word recognition, but also for tasks of attentional control. Results showed a general WBB-related improvement in cognitive performance that was consistent with a dose-response model, indicating a linear relationship between cognitive benefits and increasing WBB dose. Based on preliminary evidence, researchers suggest that a high-flavonoid diet may be highly beneficial for students. Significant limitations of the study involve the use of a relatively small sample size and the enrollment of children whose daily intake of fruits and vegetables was already relatively high, which may have potentially reduced the effects of the intervention. It would be valuable to assess the impact of WBB on the cognitive performance of children with less nutrient-dense diets. The inclusion of blood measures of flavonoid content would also be helpful for future studies.

Source: Whyte, Adrian R., Graham Schafer, and Claire M. Williams. “Cognitive effects following acute wild blueberry supplementation in 7-to 10-year-old children.” European journal of nutrition 55, no. 6 (2016): 2151-2162. Whyte AR, Schafer G, and Willams CM. Cognitive effects following acute wild blueberry supplementation in 7- to 10-year-old children. European Journal of Nutrition. 2016; 55: 2151-2162. DOI: 10.1007/s00394-015-1029-4.

Posted January 28, 2019.

Angeline A. De Leon, MA, graduated from the University of Illinois at Urbana-Champaign in 2010, completing a bachelor’s degree in psychology, with a concentration in neuroscience. She received her master’s degree from The Ohio State University in 2013, where she studied clinical neuroscience within an integrative health program. Her specialized area of research involves the complementary use of neuroimaging and neuropsychology-based methodologies to examine how lifestyle factors, such as physical activity and meditation, can influence brain plasticity and enhance overall connectivity.

References:

  1. Benton D. Micro-nutrient supplementation and the intelligence of children. Neuroscience & Biobehavioral Reviews. 2001;25(4):297-309.
  2. Lamport DJ, Dye L, Wightman JD, Lawton CL. The effects of flavonoid and other polyphenol consumption on cognitive performance: a systematic research review of human experimental and epidemiological studies. Nutrition and Aging. 2012;1(1):5-25.
  3. Miller MG, Shukitt-Hale B. Berry fruit enhances beneficial signaling in the brain. Journal of agricultural and food chemistry. 2012;60(23):5709-5715.
  4. Rendeiro C, Vauzour D, Rattray M, et al. Dietary levels of pure flavonoids improve spatial memory performance and increase hippocampal brain-derived neurotrophic factor. PloS one. 2013;8(5):e63535.
  5. Scholey AB, French SJ, Morris PJ, Kennedy DO, Milne AL, Haskell CF. Consumption of cocoa flavanols results in acute improvements in mood and cognitive performance during sustained mental effort. Journal of Psychopharmacology. 2010;24(10):1505-1514.
  6. Krikorian R, Nash TA, Shidler MD, Shukitt-Hale B, Joseph JA. Concord grape juice supplementation improves memory function in older adults with mild cognitive impairment. British Journal of Nutrition. 2010;103(05):730-734.
  7. Lamport DJ, Pal D, Moutsiana C, et al. The effect of flavanol-rich cocoa on cerebral perfusion in healthy older adults during conscious resting state: a placebo controlled, crossover, acute trial. Psychopharmacology. 2015;232(17):3227-3234.
  8. Whyte AR, Schafer G, Williams CM. Cognitive effects following acute wild blueberry supplementation in 7-to 10-year-old children. Eur J Nutr. 2016;55(6):2151-2162.