Dietary cocoa flavanols could help reverse memory decline in older adults.

A new study provides the first evidence that changes in a certain region of the brain is linked to age-related memory decline, and this can be influenced by dietary interventions, the Columbia University Medical Center reported.

The part of the brain believed to be involved in age-related memory decline (which is different than Alzheimer's) is called the dentate gyrus, but only a correlational link had been proven in the past. To prove causation the team tested whether cocoa flavanols could improve function in this part of the brain and if this eased symptoms of age-related memory decline.

To make their findings the researchers looked at 37 healthy volunteers between the ages of 50 and 69 who were put on either a high-flavanol diet (900 milligrams of flavanols a day) or a low-flavanol diet (10 mg of flavanols a day) for a period of three months. The team also performed brain imaging and memory tests.

"When we imaged our research subjects' brains, we found noticeable improvements in the function of the dentate gyrus in those who consumed the high-cocoa-flavanol drink," said lead author Adam M. Brickman, associate professor of neuropsychology at the Taub Institute.

The high-flavanol group performed significantly better on the memory test than those who were not given extra flavanol.

"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," Small said. 

The researchers noted the drinks used in the study are not the same as chocolate and patients should not increase their chocolate consumption. Exercise has also been shown to improve age-related memory problems in past studies.

The findings were published Oct. 23 in the journal Nature Neuroscience.