Health News: Randomized Clinical Study Shows That Wild Blueberry Can Improve Vascular Function And Cognitive Performance In Older Males And Females

Health News: A new European double-blind randomized controlled clinical trial has demonstrated that polyphenols from the wild blueberry is able to boost for vascular function and cognitive performance in older adults.


 Pic Credit: Maria Dryfhout/Shutterstock.com

The study was led by researchers from: King’s College London-UK, University of Reading-UK, Buchinger Wilhelmi Clinic-Germany, King’s College Hospital NHS Foundation Trust-UK and Lisbon School of Health Technology, Lisbon Polytechnic Institute-Portugal.
 
As the world's population ages, the search for effective interventions to enhance cognitive function and overall health is more critical than ever. One potential solution may lie in the realm of natural remedies, specifically wild blueberries. Wild blueberries (Vaccinium angustifolium) are a rich source of (poly)phenols, which are known for their antioxidant and anti-inflammatory properties.
 
The study team explored the potential of wild blueberry (poly)phenols to improve vascular function and cognitive performance in healthy older males and females.
 
Wild Blueberries and (Poly)phenols
Wild blueberries, native to North America, are a small, sweet fruit packed with nutrients and bioactive compounds. Among these compounds are (poly)phenols, a diverse group of plant-based molecules with significant health-promoting effects. (Poly)phenols can be classified into various subgroups, including flavonoids, phenolic acids, and stilbenes, each with their unique properties. Wild blueberries are particularly rich in anthocyanins, a type of flavonoid responsible for their vivid blue color.
 
(Poly)phenols and Vascular Function
Vascular function is essential for maintaining cardiovascular health and overall well-being. With age, blood vessels can lose elasticity and become less efficient in delivering oxygen and nutrients to the body's tissues. (Poly)phenols in wild blueberries have been shown to improve vascular function by:
 
-Enhancing endothelial function: The endothelium is the inner lining of blood vessels, responsible for regulating blood flow and maintaining vascular health. (Poly)phenols, particularly anthocyanins, can improve endothelial function by increasing the bioavailability of nitric oxide (NO), a molecule that helps blood vessels dilate and relax. This effect promotes better blood flow and reduces the risk of hypertension and cardiovascular diseases.
 
-Reducing oxidative stress: Oxidative stress occurs when an imbalance between free radicals and antioxidants causes damage to cells and tissues. (Poly)phenols from wild blueberries possess potent antioxidant properties that neutralize free radicals and protect blood vessels from oxidative damage. This protective effect may help to preserve vascular function and reduce age-related decline.
 
-Inhibiting inflammation: Chronic inflammation is linked to numerous age-related health issues, including atherosclerosis and impaired vascular fu nction. (Poly)phenols in wild blueberries can modulate inflammatory pathways, suppressing the production of pro-inflammatory molecules and reducing vascular inflammation. This anti-inflammatory effect may contribute to improved vascular health and function.
 
(Poly)phenols and Cognitive Performance
Age-related cognitive decline is a significant concern for older adults, and maintaining cognitive function is essential for healthy aging. Research suggests that (poly)phenols in wild blueberries may positively impact cognitive performance through several mechanisms:
 
-Improving cerebral blood flow: As mentioned earlier, (poly)phenols can enhance vascular function, leading to improved blood flow. This effect also extends to the brain, where increased cerebral blood flow can deliver essential oxygen and nutrients to neurons, supporting optimal cognitive function.
 
-Reducing neuroinflammation: Inflammation in the brain has been implicated in the development of neurodegenerative diseases, such as Alzheimer's and Parkinson's. (Poly)phenols from wild blueberries can modulate inflammatory responses in the brain, suppressing the production of pro-inflammatory molecules and protecting neurons from damage. This neuroprotective effect may help to maintain cognitive function in older adults.

-Enhancing neuroplasticity: Neuroplasticity refers to the brain's ability to reorganize and adapt its structure and function in response to new experiences and challenges. (Poly)phenols have been shown to promote neuroplasticity by increasing the expression of brain-derived neurotrophic factor (BDNF), a protein that supports the growth and maintenance of neurons. Enhanced neuroplasticity may contribute to improved learning, memory, and overall cognitive performance.
 
Combatting oxidative stress in the brain: Oxidative stress can lead to neuronal damage and impaired cognitive function. The antioxidant properties of (poly)phenols in wild blueberries can protect brain cells from oxidative damage, helping to maintain the structural and functional integrity of neurons.
 
Past Clinical Studies And Health News Coverages On Wild Blueberry (Poly)phenols
Several clinical studies have examined the effects of wild blueberry (poly)phenols on vascular function and cognitive performance in older adults. One such study conducted by Krikorian et al. (2010) found that daily consumption of wild blueberry juice for 12 weeks improved cognitive performance, particularly memory, in older adults with mild cognitive impairment.
https://pubmed.ncbi.nlm.nih.gov/20047325/
 
Another study by Rodriguez-Mateos et al. (2019) demonstrated that acute intake of wild blueberry (poly)phenols increased endothelial function and peripheral arterial tonometry in healthy older adults, suggesting improved vascular function.
https://pubmed.ncbi.nlm.nih.gov/30772905/
 
Others studies and coverages extolling the merits of blueberries include:
https://www.health.harvard.edu/staying-healthy/blueberries-may-help-lower-blood-pressure
 
https://medicine.yale.edu/news-article/heart-health-qanda-can-eating-blueberries-improve-blood-pressure-in-postmenopausal-women/
 
https://www.nutritioninsight.com/news/anthocyanins-for-better-heart-health-a-cup-of-blueberries-a-day-may-reduce-cvd-risk-study-finds.html
 
https://nutritionfacts.org/2022/08/30/one-daily-cup-of-blueberries-found-to-improve-cognition/
 
https://pubmed.ncbi.nlm.nih.gov/30999017/
 
In this new double-blind, parallel randomized controlled trial, 61 healthy older individuals aged 65-80 years were enrolled and every participant received either 26g of freeze-dried wild blueberry (WBB) powder (302 mg anthocyanins) or a matched placebo (0 mg anthocyanins).
 
Endothelial function measured by flow-mediated dilation (FMD), cognitive function, arterial stiffness, blood pressure (BP), cerebral blood flow (CBF), gut microbiome and blood parameters were measured at baseline and 12 weeks following daily consumption. Plasma and urinary (poly)phenol metabolites were analyzed using micro-elution solid phase-extraction coupled with LC-MS.
 
The study showed a significant increase in FMD and reduction in 24 h ambulatory systolic BP were found in the WBB group compared to placebo (0.86%; 95% CI 0.56, 1.17, p<0.001; -3.59 mmHg; 95% CI -6.95, -0.23, p=0.037; respectively).
 
Enhanced immediate recall on the auditory verbal learning task, alongside better accuracy on a task-switch task were also found following WBB treatment compared to placebo (p<0.05). Total 24 h urinary (poly)phenol excretion increased significantly in the WBB group compared to placebo. No changes in CBF or gut microbiota composition were found.
 
The study findings showed that daily intake of Wild Blueberry powder, equivalent to 178 g fresh weight, improves vascular and cognitive function, and decreases 24h ambu