Memory loss can be prevalent among the elderly but findings of a new study offer evidence that a natural compound found in cocoa can reverse age-related memory decline.

For the study published in the journal Nature Neuroscience on Oct. 26, Scott Small, from the Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and colleagues involved 37 healthy older adults who were between 50 and 69 years old.

The study participants were randomly assigned into two groups where they either received a high-flavanol diet or a low-flavanol diet for three months. Participants in the high-flavanol diet received 900 milligrams of cocoa flavanols per day while those in the low-flavanol diet had 10 milligrams of cocoa flavanols daily.

In order for the researchers to track the changes to an area of the brain called the dentate gyrus (DG) region, which is suspected to play an important role in age-related memory decline, Small and colleagues had the participants undergo brain scans before and after the study period. They also asked the participants to complete a test that would assess a type of memory that is controlled by the dentate gyrus.

The researchers found that the participants who were placed on high-flavanol diet scored significantly higher in their post-diet memory test compared with their counterparts who received low-flavanol diet.

The participants who received 900 milligrams of cocoa flavanols per day also exhibited improved memory at the end of the three-month study period relative to their own abilities before the study started.

"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.

Although flavanol are naturally found in cocoa, the researchers said that it does not mean that people should start gorging massive amounts of commercially available chocolate and cocoa products because these products typically go through processes called dutching and alkalization that strip the healthy flavanols. The study used a drink that was specially made by chocolate maker Mars.

"A high-flavanol intervention was found to enhance DG function, as measured by fMRI and by cognitive testing," the researchers wrote. "Our findings establish that DG dysfunction is a driver of age-related cognitive decline and suggest non-pharmacological means for its amelioration."

Flavanols are not only present in cocoa. They are also naturally found in tea leaves as well as in fruits and vegetables such as pomegranates and apples.