CACAO farmers have every reason to enthuse about a recent study conducted at Columbia University Medical Center (CUMC), which showed that cocoa flavanols reverse age-related memory decline.
The Philippines is a net importer of cacao, which is believed to have a variety of pharmaceutical, as well as dietary uses, with the ancient Aztec and Mayan civilizations, considering it as a “drink of the gods.”
Cacao cultivation is on the upswing in Bicol and in Mindanao, motivated in part by the rise of artisanal chocolate production in Davao and elsewhere.
The CUMC researchers clarified that the product used in the study is not the same as chocolate, and they warned against an increase in chocolate consumption as people attempt to achieve the same effect on the participants in the study.
Flavanols are naturally occurring bioactives found in cocoa but their ability to stop debilitating memory loss among people over 50 years old cannot be exploited without resorting to a special process.
Unfortunately, the process of processing, extracting, enriching and using cacao flavanols for drinks is owned and patented by Mars Inc., which also supported the CUMC research.
Most methods of processing cocoa actually remove many of the flavanols found in the raw plant.
The study, published on October 24, in the advance issue of Nature Neuroscience, discusses the first direct evidence that one component of age-related memory decline among humans is caused by changes in a specific region of the brain.
This memory decline can be arrested and the memory can be enhanced through dietary intervention using cacao flavanols.
A decline in cognitive abilities shows as people age, with the process starting in early adulthood but becomes more patent when they reach their 50s or 60s.
This memory decline is different from memory impairment caused by Alzheimer’s, which damages and destroys neurons in various parts of the brain, including the memory circuits, as well as the entorhinal cortex.
Previous work, including those of senior author Dr. Scott A. Small, had shown that changes in a specific part of the brain—the dentate gyrus—are associated with age-related memory decline, but the evidence adduced was only a correlational link, not a causal one.
To find out if the dentate gyrus is the source of age-related memory decline, Small and his colleagues tested whether compounds called cocoa flavanols can improve the function of this brain region and improve memory.
Previous studies had shown that flavanols extracted from cocoa beans improved neuronal connections in the dentate gyrus of mice.
Small is the Boris and Rose Katz Professor of Neurology in the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, the Sergievsky Center and the Departments of Radiology and Psychiatry and director of the Alzheimer’s Disease Research Center in the Taub Institute at CUMC.
A cocoa flavanol-containing test drink was prepared by Mars Inc., which has developed the expertise in retaining the flavanols found in the raw plant.
In the CUMC study, 37 healthy volunteers, aged 50 to 69, were randomized to receive either a high-flavanol diet (900 milligrams of flavanols a day), or a low-flavanol diet (10 mg of flavanols a day), for three months.
Brain imaging and memory tests were administered to participants before and after the study.
The brain imaging measured blood volume in the dentate gyrus, which shows the level of metabolism, while the memory test involved a 20-minute pattern-recognition exercise meant to assess a type of memory controlled by the dentate gyrus.
“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 Dr. Adam M. Brickman, associate professor of neuropsychology at the Taub Institute.
Brickman also noted that the high-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,” Small said.
He stressed that, soon, a larger study will be conducted to test the efficacy of the flavanols among the seniors and broader social sectors.
Flavanols are also found naturally in tea leaves and in certain fruits and vegetables, but their amounts and specific forms vary, the CUMC team said.
The precise formulation used in the CUMC study has also been shown to improve cardiovascular health.
Buoyed by these findings, the Brigham and Women’s Hospital in Boston recently launched a National Institutes of Health (NIH)-funded study of 18,000 men and women to see whether flavanols can help prevent heart attacks and strokes.
The study used a new information-processing tool developed by Dr. Usman A. Khan, a PhD student in the laboratory, and Frank A. Provenzano, a biomedical engineering graduate student at Columbia.
This tool allows the imaging data to be presented in a single, three-dimensional snapshot, rather than in individual slices.
The other innovation developed by Brickman and Small was a modification to a classic neuropsychological test, allowing the researchers to evaluate memory function localized to the dentate gyrus.
Besides flavanols, exercise has been shown in previous studies, including those of Small, to improve memory and dentate gyrus function among younger people.
However, the researchers were unable to assess whether exercise had an effect on memory or on dentate gyrus activity.
“Since we didn’t reach the intended VO2max [maximal oxygen uptake] target,” Small concluded, “we couldn’t evaluate whether exercise was beneficial in this context. This is not to say that exercise is not beneficial for cognition. It may be that older people need more intense exercise to reach VO2max levels that have therapeutic effects.”