According to a recent study, dietary cocoa flavanols - naturally occurring bioactive compounds found in cocoa - can reverse age-related memory decline in healthy older adults. This study provides the first evidence that a component of age-related memory decline is caused by changes in a specific brain region and that this type of memory decline can be improved by dietary intervention.
As people age, they typically show a loss in their cognitive abilities. For example, they may become slower at learning new things and poorer at remembering the names of new acquaintances or where they parked the car or placed their house keys. This normal age-related memory decline starts in early adulthood, but usually does not have any noticeable impact on quality of life until people typically reach their fifties or sixties. It must be noted here that age-related memory decline is different from the devastating memory impairment seen in Alzheimer's disease and other dementias.
Previous research had shown that changes in a specific part of the brain, known as the dentate gyrus, are associated with age-related memory decline. To confirm this association, researchers tested whether compounds called cocoa flavanols can improve the function of the dentate gyrus and improve memory. Flavanols extracted from cocoa beans had previously been shown to improve neuronal connections in the dentate gyrus of mice.
A cocoa flavanol-containing test drink was prepared specifically for this study. Interestingly, most commercial methods of processing cocoa remove many of the flavanols found in the raw plant. In this study, 37 healthy volunteers (aged 50-69 years) were given either a high- or low-flavanol diet for three months. Brain imaging and memory tests were administered to each participant before and after the study.
When the research subjects' brains were imaged after the study, researchers found noticeable improvements in the function of the dentate gyrus in those subjects who consumed the high-flavanol drink.
The high-flavanol group also performed significantly better on the memory test. If a participant in the high-flavanol group had the memory of a typical 60-year-old at the beginning of the study, after three months on average that person had the memory of a typical 30- or 40-year-old.
Flavonols are found naturally in tea leaves, wine and in certain fruits and vegetables along with cocoa. Interestingly, the precise formulation of cocoa flavonols used in this study has also been shown in previous research to improve cardiovascular health.