Cocoa does more than taste good, it sharpens the mind. Antioxidants occur naturally in cocoa, and a new study suggests they help the brain counter age-related memory decline.
Even in healthy people, age typically brings about some loss of memory. We experience minor lapses in short-term memory such as forgetting where the car is parked or what you went into the garage to do. This normal process actually begins early in adulthood, but only becomes noticeable as a person enters their fifties and sixties.
This expected cognitive decline, as opposed to the more severe form seen in patients suffering from dementia, can be improved by a dietary intervention, specifically, the antioxidants found in chocolate.
Earlier studies had found indirect correlations between flavanols and memory. The new study, led by a team of scientists from Columbia University, was able to pinpoint the way that the flavanols in cocoa affect the brain.
If a participant had the memory of a typical 60-year-old at the beginning of the study, after three months that person on average had the memory of a typical 30- or 40-year-old.
A brain region, the dentate gyrus, is involved in age-related memory decline. The research group tested the affect of cocoa flavanols on memory, paying close attention to the dentate gyrus.
One group of participants in the study was given a drink containing cocoa flavanols prepared specifically for the study by the Mars company, an important contribution as most methods of processing cocoa remove flavanols. Another group was given a drink without the flavanols. All the subjects were between the ages of 50 and 69.
Brain imaging and memory tests were used to assess brain function and memory.
When the researchers looked at the images of the subjects' brains, they found improvements in the function of the dentate gyrus in those who consumed the specially-formulated drink. More importantly, the cocoa-flavanol group also performed significantly better on the memory test.
“If a participant had the memory of a typical 60-year-old at the beginning of the study, after three months that person on average had the memory of a typical 30- or 40-year-old,” commented neurologist Scott A Small, Professor and director of the Alzheimer's Disease Research Center in the Taub Institute at Columbia.
While the results are exciting, they will need to be replicated in larger follow-up studies. Interestingly, this is not the first time flavanols have been associated with health benefits. The same formulation of cocoa flavanols has been linked to improvements in cardiovascular health. An NIH-funded study of 18,000 individuals has been begun to test this further.
Before indulging in Halloween candy, you should know that the product used in both the memory and cardiovascular studies is not the same as store-bought chocolate, which is not expected to produce similarly beneficial effects.
Fortunately, flavanols are also found naturally in tea leaves and in certain fruits and vegetables, but the type and amounts vary. Furthermore, like flavanols, exercise has been shown to improve memory and dentate gyrus function in younger adults.
The study is published in Nature Neuroscience.