Is the latest study linking chocolate with brain health too good to be true? Find out more about what the science is really telling us.
For those of us who are chocoholics, any news linking chocolate with health improvement is received with jubilation. And there’s been a fair amount of that lately: recent headlines have hyped the results of a new study looking at the effects of cocoa consumption on brain health. Some publications have gone so far as to say that drinking cocoa can “stave off Alzheimer’s” or “sharpen seniors’ brains.” Much as we might want that to be true, a closer look at the study reveals that much more modest conclusions are in order. Nevertheless, there is still reason to continue studying chocolate’s potential health benefits.
What the Study Revealed About Cocoa and Brain Health
The study in question, which was published in the journal Neurology a couple of weeks ago, seemed to demonstrate a potential link between brain health and the unique antioxidant compounds in cocoa known as flavanols. Seniors consumed two cups of cocoa a day for one month—one group consuming cocoa high in flavanols and another consuming cocoa low in flavanols. The researchers were somewhat surprised to find no significant differences between the two groups—it didn’t seem to make a difference whether subjects consumed low-flavanol or high-flavanol cocoa. And there wasn’t much change over the course of the study.
However, there was one interesting finding, and that’s what the headlines have latched onto. In both groups, subjects who had impaired blood flow to the brain at the beginning of the study showed improved blood flow and better cognitive performance at the end of the study period. Better blood flow brings more oxygen and sugar to the brain, which is vital for cognitive function—a relationship scientists call “neurovascular coupling” or NVC.
The Problem with the Headlines
News outlets eager to break the next big story on chocolate and brain health were sometimes a bit hyperbolic in their interpretation of the study’s results. The lead author, Farzaneh Sorond, a neurologist at Brigham and Women’s Hospital in Boston, has pointed out that the impact of cocoa was just one small part of the research, and one that will need further exploration.
“How cocoa results in improved neurovascular coupling, we don’t know,” says Sorond. “We also don’t know what it is in cocoa that is beneficial; is it the flavanols, the caffeine, the theobromine? In our study there was no difference between the flavanol poor and rich compounds in terms of benefit. Does this mean the flavanols are not important or does it mean that just a little bit of flavanol is enough?”
The UK’s National Health Service points out that the study did not include a control group that specifically addressed the cocoa question—a set of subjects that did not drink any cocoa, which could be compared to the groups that did drink cocoa. Also, the study did not include subjects who actually had Alzheimer’s disease or other forms of dementia, so headlines touting cocoa’s effect on those conditions may be a bit premature. In fact, Sorond points out on NPR that there’s no reason to add more cocoa or chocolate to your diet just yet: “adding the extra calories, sugar and fat that comes with chocolate and cocoa carries additional health hazards which may offset any possible brain benefits.”
The Future of Chocolate and Cognitive Health
There is good news here for future research, though: studies designed specifically to look at cocoa’s effects on brain health may well turn up more specific links. The National Health Service concludes, rather cautiously, that “This study raises the possibility that there is something in cocoa – not necessarily flavanol – that may improve blood flow inside the brain. Based on this study it is not possible to predict whether this possibility will lead to an effective preventative treatment for dementia or cognitive decline.” However, there have been other recent promising studies in animal subjects, as well as a 2012 study in Italy that showed positive effects of cocoa consumption on seniors with mild cognitive impairment. So keep your eyes on the headlines, because there may be some real news on the subject to report in the near future.
What’s your opinion—do you think the latest link between chocolate and cognition is reason for hope, or just more health hype? Feel free to join the discussion in the comments.