Blueberries Improve Cognitive Function

Blueberries Are Food for the Brain: Science Shows Cognitive Function Enhanced in Kids Who Eat Blueberries

Do blueberries improve cognitive function in children?

Classical music, playdates, IQ puzzles, lots of books, and blueberries are just a few of the items on the to-do list for parents who want to give their children every advantage when it comes to their mental ability. The quest for brain health and enhanced cognitive function is a lifelong pursuit for many that begins, for some, during childhood. As a parent of three, I want to know proven strategies to support healthy cognition so my children can have the best possible start to life. Eating blueberries to boost brain function is a popular strategy among the young and old, but what does the science say? Do blueberries actually improve cognitive function in children?

Flavanoids: Blueberry’s Brain-Boosting Compounds

Just what is it about blueberries that make them good for the brain? Blueberries contain high levels of flavonoids, a sub-class of polyphenols, which research suggests have various health-promoting and brain-boosting benefits (1). While a variety of plant foods contain flavonoids, berries are the main source of anthocyanins (one of several types of flavonoids found in plant foods) in the human diet (2). In both human and animal studies, participants experienced improved vascular and cognitive function following flavonoid consumption. Research suggests that flavonoid consumption may be linked to improved memory, attention, and cognitive function throughout the life cycle.

How to Flavonoids Improve Cognitive Function?

While science is not certain of the mechanism behind the brain-boosting affects of flavonoid-rich foods, researchers hypothesize that flavonoids protect nerve cells from stress, help to increase blood flow to brain, or that they have a positive effect on the brain’s signaling pathways (2, 3). While the link between a healthy diet and cognitive development and function in children is well-established, there was no research looking specifically at brain function in children eating blueberries prior to 2015 (3).

Recent Studies Show Blueberries Give Kids’ Brains a Boost

Recent research has provided now evidence that kids who eat blueberries may have a cognitive advantage. In 2015 a pilot study involving 14 8- and 9-year-old children investigated whether or not the cognitive benefits seen in previous (animal and adult) studies after eating blueberries would extend to children. Children consumed either a blueberry drink or a matched vehicle (a drink with comparable nutrients and flavor, but lacking whole blueberries or flavonoids). Two hours after consuming the drink, children took five tests measuring cognitive function. After a seven-day washout period, the two groups were switched with those who had received the blueberry drink receiving the vehicle and vice versa. Results from this study were impressive. Children who drank the blueberry drink had a significantly improved ability to recall a list of previously learned words. The researchers concluded that consuming blueberries may help children more effectively encode items to memory (3).

            Several studies followed this ground-breaking research exploring the cognitive benefits of blueberry consumption in children. Another study published in the European Journal of Nutrition in 2016 investigated if there was a time-course and dose-response relationship between consuming blueberries and cognitive benefits. Twenty-one children age 7-10 years-old old drank either a placebo or blueberry drink containing 15 or 30 grams of freeze-dried wild blueberry powder. Various cognitive tests were administered at baseline and 1.15 hours, 3 hours, and 6 hours after the drinks were consumed. After consuming the blueberry drink, children had significant improvements in multiple cognition tests. Even more amazing, cognitive performance improved across all measures in a dose-response manner. Children had the worst performance after consuming the placebo and the best performance following the highest dose of blueberries (2).

         Another study challenged children with varying levels of cognitive demand across trials in order to see if careful manipulation of the task would illuminate possible benefits of consuming blueberries. Twenty-one children consumed either a placebo or 30 grams of freeze dried blueberry powder and were tested three hours later. Those who drank blueberries performed significantly faster than those consuming placebo and the effect was most pronounced with more the cognitively demanding trials. The researchers concluded that blueberry consumption can enhance cognitive function, but of perhaps equal importance is the demand and complexity of the task (4).

Quicker Brain, Improved Memory: Real World Benefits of Blueberries

Evidence was mounting for the ability of blueberries to enhance cognition in children, but do these results translate into real-world educational settings? A 2019 study published in the European Journal of Nutrition set out to assess which aspects of memory and executive function would be impacted by blueberry consumption and whether blueberries would benefit reading ability in children. This was the largest study on children to date with 54 healthy 7-10 year-olds participating. The children consumed either a 200 ml placebo or a blueberry drink with 253 mg of anthocyanins and were assessed at baseline and two hours after their drink. Not surprisingly, children who consumed the blueberry drink exhibited significantly quicker accurate responses to the executive function tests as well as enhanced verbal memory performance. Despite these enhancements however, researchers found no significant benefits for reading measures (5).

Another study published in Food and Function in 2020 subjected 17 children, ages 7-10 year-old, to a battery of executive function task and memory tests after consuming either a placebo or blueberry drink in order to further examine the impact of a blueberry intervention. The study found shorter reaction times for executive function and memory tasks, further strengthening the evidence for the cognitive benefits of blueberry consumption in children (6). But what about the effects of consuming blueberries over time?
The following year a pilot study was the first to examine the effects of blueberry consumption in children over time and the first to examine metabolite profiles of children after consuming blueberries. In this study 15 healthy 7-10 years olds received either a blueberry drink or a matched placebo daily for four weeks. Researchers collected urine samples before and after the four-week intervention in order to measure polyphenol metabolites. Results indicate those who consumed the blueberry drink performed better on cognitively demanding tasks(7).

Blueberry Research in Children is Just Beginning

As a relatively young area of research, there are many opportunities for further study to elucidate the mechanisms behind the cognitive improvements conferred by blueberries, as well as the real-world applicability for children in educational settings. Research opportunities include investigating the effects of chronic supplementation (consuming blueberries over a longer period of time), utilizing more sensitive reading measures as well as other real-world applications such as in schools, research considering which areas of the brain relate to the cognitive tasks and research investigating mechanisms of action (i.e. increased cerebral blood flow) that use biomarkers or other technologies to objectively measure the physiological responses to blueberry consumption in children.

Blueberries Give Brains a Boost

Research investigating the effect of blueberry consumption on cognitive function in children is relatively new and limited, yet the evidence so far is promising. When this research is viewed alongside prior studies investigating the health and cognitive benefits of polyphenols and flavonoids in vitro, in animals, and in human adults, the case for the brain-boosting power of blueberries is strong. All studies to date have demonstrated that consuming blueberries improves various aspects of cognition in children. In light of the evidence, I’ll continue to feed my children blueberries as often as possible—after all, what mother wouldn’t want to give their child’s brain power a little boost?

References: 
1. Pérez-Jiménez, J., Neveu, V., Vos, F., & Scalbert, A. (2010). Identification of the 100 richest dietary sources of polyphenols: an application of the Phenol-Explorer database. European journal of clinical nutrition, 64 Suppl 3, S112–S120. https://doi.org/10.1038/ejcn.2010.221 

2. Whyte, A. R., Schafer, G., & Williams, C. M. (2016). Cognitive effects following acute wild blueberry supplementation in 7- to 10-year-old children. European journal of nutrition, 55(6), 2151–2162. https://doi.org/10.1007/s00394-015-1029-4

3. Whyte, A. R., & Williams, C. M. (2015). Effects of a single dose of a flavonoid-rich blueberry drink on memory in 8 to 10 y old children. Nutrition (Burbank, Los Angeles County, Calif.), 31(3), 531–534. https://doi.org/10.1016/j.nut.2014.09.013

4. Whyte, A. R., Schafer, G., & Williams, C. M. (2017). The effect of cognitive demand on performance of an executive function task following wild blueberry supplementation in 7 to 10 years old children. Food & Function, 8(11), 4129–4138. https://doi.org/10.1039/c7fo00832e 

5. Barfoot, K. L., May, G., Lamport, D. J., Ricketts, J., Riddell, P. M., & Williams, C. M. (2019). The effects of acute wild blueberry supplementation on the cognition of 7-10-year-old schoolchildren. European journal of nutrition, 58(7), 2911–2920. https://doi.org/10.1007/s00394-018-1843-6 

6. Whyte, A. R., , Lamport, D. J., , Schafer, G., , & Williams, C. M., (2020). The cognitive effects of an acute wild blueberry intervention on 7- to 10-year-olds using extended memory and executive function task batteries. Food & Function, 11(5), 4793–4801. https://doi.org/10.1039/c9fo02284h

7. Barfoot, K. L., Istas, G., Feliciano, R. P., Lamport, D. J., Riddell, P., Rodriguez-Mateos, A., & Williams, C. M. (2021). Effects of daily consumption of wild blueberry on cognition and urinary metabolites in school-aged children: a pilot study. European journal of nutrition, 60(8), 4263–4278. https://doi.org/10.1007/s00394-021-02588-y