“Importantly, similar results were observed for individual cognitive domains, including visuospatial processing/reasoning and attention, processing and psychomotor speed, verbal speed and fluency, episodic memory, and working memory,” wrote researchers from Jagiellonian University Medical College in Poland and other institutions in Europe and China.
The analysis of 59 randomized controlled trials, mostly concerning older adults, found no relation between effect and anthocyanin dose, however the duration of supplementation was significant: longer trials resulted in greater improvements than shorter ones.
“These findings suggest that the intake of anthocyanin-rich foods may exert positive effects on health over a longer time consumption rather than excessive daily doses, which is in line with the biological rationale that food compounds are naturally designed to be consumed within certain dose boundaries and that may exert effects on health over an established chronic exposure,” the researchers wrote.
“Overall, the results reported in this study support the hypothesis that plant-based dietary patterns rich in anthocyanins may be associated with better cognitive functioning and slower cognitive decline,” they added.
They noted that including anthocyanin-rich foods such as berries and supplementing juices or extracts may be a potential strategy to improve cognition in older adults.
How plant foods may protect the brain
Evidence suggests that both genes and the environment likely influence the development of and susceptibility to neurodegenerative conditions.
Studies show that diet and lifestyle factors can induce epigenetic modifications in key pathways and genes related to Alzheimer’s disease, and antioxidants may reduce oxidative stress linked to cognitive decline.
Phytochemicals in plant foods, such as polyphenols, have been shown to modulate neuroinflammation, enhance neurogenesis, and support vascular health. These properties may help prevent cognitive decline, and the consumption of phytonutrients has been associated with a reduced risk of development.
The current study notes that the mechanisms through which anthocyanins exert cognitive benefits are multifactorial and involve several key processes. These include promoting nitric oxide production to enhance blood flow to the brain, reducing oxidative damage to cellular components and protecting neurons, and modulating inflammatory pathways.
Anthocyanins may also enhance synaptic function and promote neurogenesis, supporting memory and spatial navigation.
In addition, the researchers noted that anthocyanins undergo extensive transformation by the gut microbiota, reaching the colon in their aglycone forms, which are more readily degraded by microbes into other compounds such as phenolic acids with neuroprotective effects.
Anthocyanin intake may also modulate gut bacteria, leading to increased short-chain fatty acids, reduced inflammation, and better systemic and brain health.
“Therefore, the microbial shifts promoted by anthocyanins may partly explain their observed effects on mood regulation, cognitive performance, and reduced risk of neurodegenerative disorders,” the researchers wrote, noting that it is unclear if the effects are a direct action of anthocyanins or an indirect action of the gut microbiota.
Source: GeroScience, 2025, doi: 10.1007/s11357-025-02008-7. “The effect of anthocyanins and anthocyanin-rich foods on cognitive function: a meta-analysis of randomized controlled trials.” Authors: A. Micek, et al.
