Researchers say that cocoa flavanols can improve cognitive function.
Additionally, researchers found that regular, long-term intake of cocoa flavanols may protect against cognitive decline.
Flavanols are naturally occurring compounds found in various types of plants, with some of the highest levels found in the beans of the cocoa tree.
Flavanols have antioxidant properties, meaning that they have the ability to reduce the effects of cell damage caused by oxidative stress.
But the benefits of flavanols do not end there. A new review - recently published in the journal Frontiers in Nutrition - suggests that cocoa flavanols could benefit cognitive functioning.
The research was conducted by Valentina Socci, of the University of L'Aquila in Italy, and colleagues.
Rapid improvements in cognition
Previous studies have suggested a link between the intake of cocoa flavanols and better cognitive function, with dark chocolate often cited as the best source.
For the new research, Socci and team wanted to delve deeper into the brain benefits of cocoa flavanols: what specific cognitive functions are affected by cocoa flavanols? And are the effects immediate?
The researchers sought to answer these questions and more by conducting an in-depth review of existing studies looking at the cognitive effects of cocoa flavanols.
In particular, the team looked at how cocoa flavanols affect cognitive functioning over time and within hours of consumption.
The researchers found that, while only a small number of randomized controlled trials have looked at the short-term effects of cocoa flavanols on cognitive function, they do point to some significant benefits.
The team uncovered evidence of a link between consumption of cocoa flavanols and almost immediate improvements in working memory. One study, for example, identified working memory improvements in young adults just 2 hours after consuming 773 milligrams of cocoa flavanols.
In another study, researchers found that consumption of cocoa flavanols appeared to offset cognitive impairment caused by a night of sleep deprivation.
However, the authors note that the reported acute effects of cocoa flavanols were dependent on the type of cognitive assessments that the studies used, as well as the length of these assessments. They found that it required highly demanding cognitive tests to detect the most subtle benefits of cocoa flavanol consumption.
Elderly adults reap greatest benefits
On looking at the long-term effects of cocoa flavanol consumption, the researchers found that the majority of studies looking at this association had been conducted in elderly adults.
The review suggests that a daily intake of cocoa flavanols - for at least 5 days and up to 3 months - posed the greatest benefits for cognitive function, leading to improvements in attention, processing speed, verbal fluency, and working memory.
Socci and team note that these benefits were strongest for elderly adults who already had mild cognitive decline or other memory impairments when the studies began - a finding that surprised the researchers.
"This result suggests the potential of cocoa flavanols to protect cognition in vulnerable populations over time by improving cognitive performance," say Socci and co-author Michele Ferrara, also of the University of L'Aquila.
"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," they continue. "This structure is particularly affected by aging and therefore the potential source of age-related memory decline in humans." The researchers add:
"Regular intake of cocoa and chocolate could indeed provide beneficial effects on cognitive functioning over time."
The team cautions, however, that we should avoid eating too much chocolate, since it is high in calories and sugar. Still, the results suggest that when it comes to cognitive function, a little bit of chocolate could do wonders.