The Alzheimer's Society has warned that longer term studies are needed before drawing conclusions about the benefits of cocoa milk drinks for improving cognitive function.
A study funded by the Mars confectionary company found that consumption of a drink containing flavanols was associated with improvements in motor responses and working memory.
Those who consumed greater amounts of flavanols also performed better on overall cognitive scores too.
However, Alzheimer's Society director of research professor Clive Ballard urged caution about drawing "firm conclusions" about the significance of benefits from consuming food for cognitive function.
"From what we know at the moment, the best ways to protect our hearts and brains are to eat a healthy diet, take regular exercise and not smoke," he said.
Previous research has shown that flavanols could protect nerve cells. Professor Ballard affirmed that small preliminary studies have suggested a link between flavanols and improvement in cognitive function among older people.
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