The study, published in Neuroscience & Biobehavioral Reviews , notes that cocoa products and chocolate have recently been recognized as a rich source of flavonoids that provide potent antioxidant and anti-inflammatory agents -"with established benefits for cardiovascular health but largely unproven effects on neurocognition and behaviour."
Led by Alexander N. Sokolov from the University of Tübingen Medical School, Germany, the research team noted that while 'a few' observational and intervention studies appear to back suggestions that cocoa flavanols have beneficial effects on brain functioning and mood in the long term - evidence for any immediate effect of the compounds "remains limited and inconclusive, but warrants further research."
Sokolov and his team suggest that brain imaging studies will be central to any effort to elucidate further the long-term and short-term effects of cocoa flavanols.
"Future research has to combine functional neuroimaging techniques such as fMRI, EEG and MEG with neurocognitive and behavioral correlates to uncover long lasting and immediate effects of chocolate consumption on human cognition, mood, and behaviour," said the team.
Reports on chocolate's health benefits are dated back as far as Aztec and Maya medical practice and ever since, anecdotal evidence has been abundant on chocolate effects on health.
However it was not until the late 20th century that the supposed health benefits of chocolate have increasingly drawn a scientific interest - eventually leading to an approval by the European Food Safety Agency (EFSA) for a health claim relating to dark chocolate with high flavanol content and its impact on "maintenance of normal endothelium-dependent vasodilation."