Studies Confirm that Diet Rich in Polyphenols Improves Cognition and Brain Health

In the 21st-century, life expectancy is much higher than it was in the past.

However, this also means that humans are at an increased risk of age-related diseases, like cognitive decline.

Cognitive decline is a complex process that depends on many factors, but it’s mostly associated with damage caused by oxidative stress and inflammatory processes involving neuronal cells.

So, What Can Be Done?

One way to counteract this damage is with compounds that have strong antioxidant properties, like polyphenols.

Polyphenols are chemical compounds mainly found in fruit, vegetables, legumes, spices, coffee, tea, and cocoa.

Having this in mind, a group of researchers from Germany, Tunisia, the USA, and France published a meta-analysis of clinical studies on polyphenols that focused on young and middle-aged adults who haven’t developed symptoms of cognitive decline.

They examined the effects of both a single-dose and a prolonged intake of different types of polyphenols on different cognitive parameters.

Let’s See the Results

The goal of this meta-analysis was to examine the neuroprotective effects of polyphenols on age groups whose organs are not yet damaged and are more likely to benefit from the anti-aging effects of polyphenols than the older adults.

The single-dose intake of polyphenol supplements had a positive effect on multiple cognitive functions, such as reaction time, concentration and memory, and mental fatigue. The tests for memory and concentration were significantly improved. Mental performance during high-demanding tasks was also better, as were basic attention abilities and psychomotor speed.

For the prolonged intake, the results indicate that a single dose of 250-500mg a day showed no significant changes, but doses higher than 500mg and with higher bioavailability showed some very promising results. For example, there was a notable improvement in short and long-term memory, mental flexibility, planning, and letter fluency.

Their Conclusion

The general conclusion is that the positive effects of polyphenols seem to depend on the dosage, and on whether the supplementation is single-dose or prolonged.

The findings indicate that single-dose intake is more beneficial, especially at higher doses (above at least 250mg/day), whereas for prolonged administration, higher doses (above 500mg/day) and/or higher bioavailability is needed for neuroprotective action.

The Takeaway

There have been numerous studies proving the positive effects of polyphenols, not only on general health but on brain health as well.

It’s obvious that increasing your intake of polyphenol-rich foods would certainly be beneficial for you, but it remains to be seen what future studies will show in terms of the intake of polyphenol supplements.

Resource: Ammar, A.; Trabelsi, K.; Boukhris, O.; Bouaziz, B.; Müller, P.; M Glenn, J.; Bott, N.T.; Müller, N.; Chtourou, H.; Driss, T.; Hökelmann, A. Effects of Polyphenol-Rich Interventions on Cognition and Brain Health in Healthy Young and Middle-Aged Adults: Systematic Review and Meta-Analysis. J. Clin. Med. 2020, 9, 1598. DOI: https://doi.org/10.3390/jcm9051598