Chocolate has been credited with everything from lowering blood pressure to improving cholesterol ratios. Now Columbia University researchers have added memory-loss protection to the list – at least, if you can consume massive amounts of cocoa.
The study, published in the journal Nature Neuroscience, reports naturally occurring chemicals in cocoa called flavanols aid blood flow in the brain, enhancing connections to a region key to memory function.
The upshot? A small group of people who consumed a vast quantity of flavanols for three months showed improvements on a test of visual memory equivalent to a 60-year-old performing like a 30- or 40-year-old.
Not a license to devour candy bars
But "hold that chocolate bar," The Washington Post reported. "The researchers also warn that the compound found in cocoa exists only in minuscule amounts in the average chocolate bar compared with the amount used in the study, so gorging on chocolate in the name of health and improving one’s memory could backfire."
“It would make a lot of people happy, but it would also make them unhealthy,” Scott A. Small, a professor of neurology and director of the Alzheimer’s Disease Research Center at the Taub Institute at Columbia University Medical Center, told the newspaper.
Indeed, the test drink was prepared by the candy bar company Mars, Inc. The company also helped fund the research. Flavanols are usually lost during processing, leaving an average bar of chocolate with about 40 milligrams, but the test drink contained 900 milligrams. (Unsweetened chocolate, according to the USDA, contains much higher levels of flavanols than the average chocolate bar.)
The researchers used brain scans to compare the group getting 900 milligrams of flavanols to another group getting just 10 milligrams a day. The scans specifically noted blood volume in an area of the hippocampus called the dentate gyrus, which controls a certain type of memory.
Brain's 'dentate gyrus' influences age-related memory loss
In fact, though not quite as enticing for chocolate lovers, the study showed an "even more important" finding that "offers the first direct evidence that memory deteriorates with age because of changes in the dentate gyrus," Small told The Washington Post. Previous research had shown a connection between the dentate gyrus and memory loss, but this study is the first to show a causal link, the newspaper said.
Small said he studied the flavanol compounds in the context of normal age-related memory loss, not the severe memory loss implicated in Alzheimer's disease or dementia.
“This test reflects the kind of complaints I hear from relatively healthy older individuals who say, ‘If I met someone new today, I’m not sure I would recognize them on the street tomorrow,’” Small told Time.
Some pointed out that the type of memory the study pinpointed is narrowly defined. “Only reaction times, and not accuracy of performance, were actually improved and being faster without being more accurate is not always an advantage,” Dr. Liz Coulthard, a senior lecturer in dementia neurology at the University of Bristol, told The Independent.
While this research waits to be replicated by a larger study, it provides an early indication that diet can improve aging processes, Time reported. And more good news for chocoholics may be forthcoming: The National Institutes of Health is co-funding a big study of cocoa flavanols — involving 18,000 men and women — set to begin in early 2015, the magazine pointed out.
“The cocoa flavanols are very promising and exciting in terms of their potential role for preventing heart disease, stroke and other vascular outcomes,” Dr. JoAnn Manson, a professor at Harvard Medical School who will be co-directing the study, told Time.