Daily fruit and vegetable extracts may boost brain power

By Dr. Chinta SidharthanReviewed by Lily Ramsey, LLMFeb 11 2025

A new study reveals that polyphenol-rich nutraceuticals enhance cognitive performance and increase neuroprotective biomarkers, offering a promising dietary approach to brain health.

Study: Impact of Polyphenol-Rich Nutraceuticals on Cognitive Function and Neuroprotective Biomarkers: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Image Credit: Light Stock/Shutterstock.com

Could a daily dose of fruit and vegetable extracts sharpen your mind? A new study published in Nutrients suggested that polyphenol-rich nutraceuticals can enhance cognitive performance and boost neuroprotective biomarkers.

By analyzing the effects of a plant-based supplement on brain function, the team of researchers from Spain uncovered promising insights into how diet influences mental agility and long-term brain health.

Diet and cognitive health

Cognitive decline is a growing concern, particularly as life expectancy rises and the aging population grows. Evidence from various studies has suggested that diet plays a crucial role in brain health.

Polyphenols, which are natural compounds found in fruits and vegetables, have been linked to reduced oxidative stress and improved neuronal function.

These bioactive molecules are known to cross the blood-brain barrier and influence brain-derived neurotrophic factor (BDNF) and cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), both of which are essential for memory, learning, and synaptic plasticity.

Despite these promising findings, the precise relationship between polyphenol intake and cognitive function remains unclear since most studies have focused on general dietary patterns rather than specific nutraceutical interventions.

Understanding more about whether polyphenol-rich products can enhance cognitive abilities and support long-term neurological well-being could offer new strategies for preventing neurodegenerative diseases through accessible, nutrition-based solutions.

The current study

To address this gap, the researchers conducted a randomized, double-blind, placebo-controlled clinical trial to examine how polyphenol-rich nutraceuticals affect cognitive function.

A total of 92 participants, both male and female, were enrolled in this crossover design study, where each participant received both the active supplement and a placebo at different periods. Each treatment phase lasted 16 weeks, with a four-week washout period in between to eliminate any residual effects.

The tested supplement, Juice Plus+ Premium®, contained concentrated powders from fruits, vegetables, and berries, offering a broad spectrum of polyphenolic compounds. The participants consumed six capsules daily.

The placebo consisted of microcrystalline cellulose, which matched the appearance and dosage of the active supplement to maintain blinding.

The researchers used three standardized tests to assess cognitive performance — the Stroop Test to assess inhibitory control and selective attention, the Trail Making Test to evaluate processing speed and cognitive flexibility, and the Reynolds Intellectual Screening Test or RIST, which gauged verbal memory and logical reasoning.

Additionally, blood samples were collected to measure BDNF and CREB levels — the two key biomarkers associated with synaptic plasticity and neuroprotection. The researchers used enzyme-linked immunosorbent assays (ELISA) to quantify these biomarkers.

They also performed various statistical analyses to compare the cognitive test scores and biomarker levels between the placebo and supplement phases, accounting for potential confounding factors such as sleep, diet, and exercise.

Major outcomes

The results suggested that participants who consumed the polyphenol-rich nutraceutical demonstrated significant improvements in cognitive performance compared to the placebo group.

The Stroop Test scores indicated enhanced attention and inhibitory control, while RIST results suggested improvements in logical reasoning and memory. The Trail Making Test also revealed increased cognitive flexibility, highlighting the supplement's potential to boost overall mental agility.

Furthermore, the ELISA results showed a notable increase in BDNF and CREB levels among participants who took the active supplement. BDNF is a protein that is essential for neuronal growth and survival, and its levels were significantly elevated, reinforcing its role in synaptic plasticity and long-term memory formation.

Additionally, CREB, a transcription factor involved in learning processes, also showed increased levels, supporting its function in cognitive enhancement.

Importantly, the correlation between improved test scores and higher biomarker levels suggested that polyphenols may directly influence brain function rather than merely offering general health benefits.

While the study focused on healthy adults, the findings also raised questions about whether similar interventions could benefit populations at risk for cognitive decline, including older adults and individuals with neurodegenerative conditions.

Despite the promising results, the study did have some limitations. The trial duration was relatively short, and the long-term effects of such supplements remain uncertain. Additionally, while the supplement contained a diverse range of polyphenols, the specific compounds responsible for the observed benefits could not be identified.

Future research could explore whether certain polyphenols exert stronger neuroprotective effects than others and assess the sustainability of these cognitive improvements over time.

Conclusions

To summarize, this study highlighted the potential of polyphenol-rich nutraceuticals to enhance cognitive performance and support brain health. By increasing levels of key neuroprotective biomarkers, these supplements may also offer a practical dietary approach to improving mental agility.

While further research is needed to confirm long-term benefits and identify specific active compounds, these findings reinforced the role of nutrition in maintaining cognitive function and preventing age-related decline.