A balanced diet is chocolate in both
hands -- a phrase commonly used to justify ones chocolate snacking behavior. A
phrase now shown to actually harbor some truth, as the cocoa bean is a rich
source of flavanols: a class of natural compounds that has neuroprotective
In their recent review published in
Frontiers in Nutrition, Italian researchers examined the available literature
for the effects of acute and chronic administration of cocoa flavanols on
different cognitive domains. In other words: what happens to your brain up to a
few hours after you eat cocoa flavanols, and what happens when you sustain such
a cocoa flavanol enriched diet for a prolonged period of time?
Although randomized controlled trials
investigating the acute effect of cocoa flavanols are sparse, most of them
point towards a beneficial effect on cognitive performance. Participants
showed, among others, enhancements in working memory performance and improved
visual information processing after having had cocoa flavanols. And for women,
eating cocoa after a night of total sleep deprivation actually counteracted the
cognitive impairment (i.e. less accuracy in performing tasks) that such a night
brings about. Promising results for people that suffer from chronic sleep
deprivation or work shifts.
It has to be noted though, that the
effects depended on the length and mental load of the used cognitive tests to
measure the effect of acute cocoa consumption. In young and healthy adults, for
example, a high demanding cognitive test was required to uncover the subtle
immediate behavioral effects that cocoa flavanols have on this group.
The effects of relatively long-term
ingestion of cocoa flavanols (ranging from 5 days up to 3 months) has generally
been investigated in elderly individuals. It turns out that for them cognitive
performance was improved by a daily intake of cocoa flavanols. Factors such as
attention, processing speed, working memory, and verbal fluency were greatly
affected. These effects were, however, most pronounced in older adults with a starting
memory decline or other mild cognitive impairments.
And this was exactly the most
unexpected and promising result according to authors Valentina Socci and
Michele Ferrara from the University of L'Aquila in Italy. "This result
suggests the potential of cocoa flavanols to protect cognition in vulnerable
populations over time by improving cognitive performance. If you look at the
underlying mechanism, the cocoa flavanols have beneficial effects for
cardiovascular health and can increase cerebral blood volume in the dentate
gyrus of the hippocampus. This structure is particularly affected by aging and
therefore the potential source of age-related memory decline in humans."
So should cocoa become a dietary
supplement to improve our cognition? "Regular intake of cocoa and
chocolate could indeed provide beneficial effects on cognitive functioning over
time. There are, however, potential side effects of eating cocoa and chocolate.
Those are generally linked to the caloric value of chocolate, some inherent chemical
compounds of the cocoa plant such as caffeine and theobromine, and a variety of
additives we add to chocolate such as sugar or milk."
Nonetheless, the scientists are the
first to put their results into practice: "Dark chocolate is a rich source
of flavanols. So we always eat some dark chocolate. Every day."
"Cocoa and chocolate are not just treats -- they are good for your
cognition. " ScienceDaily, 29 June, 2017.
Socci et al., Enhancing Human
Cognition with Cocoa Flavonoids. Frontiers in Nutrition, 2017. DOI: 10.3389/fnut.2017.00019