Recent evidence suggest that polyphenols found in blueberries may have benefits for human health, particularly cognitive function. In this study, the effects of a wild blueberry treatment (WBB) made from freeze-dried blueberry powder containing 264 mg anthocyanins (equivalent to 178 g of fresh weight blueberries) versus a macronutrient and micronutrient matched placebo (0 mg anthocyanins), consumed daily for 12 weeks, was investigated. The study design was a double-blind, parallel RCT with a study population consisting of 61 healthy older adults aged between 65-80. Outcome measures included cognitive function, vascular function and cerebral blood flow. Blood and 24 h urine samples were also collected to analyse (poly)phenol metabolites in urinary and plasma samples to give us an insight into the compounds’ bioavailability in the human body. Finally, faecal samples were taken and the BluFlow study aims to explore whether there may be any composition and quantity change of strains associated with improvements in cognitive health within the WBB group and/or control group. 


Cognitive function was assessed at baseline and at 12 weeks post-intervention, using a battery consisting of 4 tasks measuring a range of cognitive functions. The tasks included Rey Auditory Verbal Learning Test (RAVLT) to measure immediate and delayed episodic memory, Corsi Block Tapping Task to measure visuospatial working memory, Serial subtraction tasks to measure working memory, and Switching Task to measure executive function. Additionally, transient mood was measured using the positive and Negative Affect Schedule (PANAS), a validated scale-rating mood questionnaire.


Linear Mixed modelling analysis with baseline performance as a covariate, revealed that accuracy scores for the switching task targeting executive function, significantly improved for the WBB group compared to placebo at 12 weeks (F(1,90.12)=5.13, p=0.026)). Additionally, immediate recall measure (AVLT) examining short-term recall memory revealed a significant improvement for the WBB compared to placebo at 12 weeks (F(1,46)=4.321, P=0.043)). No other significant effects were observed for any other cognitive measures for the blueberry group. 


This data suggests that chronic wild blueberry intervention may improve executive functioning and episodic memory processes in older adults. This, coupled with improvements in vascular health, may give us an insight into the mechanism of action behind polyphenol’s effect on cognition. However, further research is necessary in order to investigate WBB’s effect on other cognitive domains.

Chronic effects of wild blueberry (poly)phenols on cognitive function in healthy older individuals: the BluFlow study

The gastrointestinal tract is amongst the most densely populated ecosystems on earth, home to an abundant and diverse collection of microbial species, not just bacteria but also Archaea, viruses, fungi etc. Significant interest in this area has been sparked in recent years by an appreciation of the importance of the gut microbiota in the health of the host, and this has led to the microbiome of humans and animals being investigated in depth. Studies have drawn links between host nutrition, the gut microbiota and metabolic and immune functions, which in consequence affect physiology.



The first investigations of the structure of the microbiota were culture-based, however the introduction of sequencing technologies such as Sanger sequencing and subsequent development of 454 sequencing and metagenomics approaches have become the mainstay of microbiota studies. The creation of reference databases and analysis software has provided invaluable tools for assigning taxonomy to generated data. Great progress in characterising the structure of the microbiome recently has paved the way for ongoing and future studies on the functional interactions between the microbiota and the host. Studies on the function of the microbiota are critical in understanding the role of the microbiota in human homeostasis and disease pathogenesis.



The conference will be presenting the latest advancements in gut microbiome and health research. It will bring together experts who are driving technological advancements and striving to understand how nutrition impacts gut microbiome and the interactions between gut microbiome and health.



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Recordings of the conference will be available until 13 April 2021.