Well, according to the Daily Telegraph and a conference presentation it can. It all seems a little bit flakey to me.
Apparently, “Mental arithmetic became easier after volunteers had been given large amounts of compounds found in chocolate, called flavanols, in a hot cocoa drink.” The report is based on findings that were presented at the British Psychological Society’s annual conference in Brighton. Here’s what they did: 30 volunteers were asked to count backwards in groups of three from a random number between 800 and 999 generated by a computer. Here’s what they found: it turned out that the volunteers “could do the calculations more quickly and more accurately after they had been given the drink.” According to the report, “The findings also show that the volunteers did not get as tired doing the calculations if they had been given the cocoa drink[*], despite being asked to do them over and over for an hour.” However, “the same was not true when the group was asked to count backwards in groups of seven, which the researchers described as a more complex task”[#]
Interestingly, the authors of the paper ascribe the effects of the cocoa drink to something they call “flavanol”. Flavanols are found in fruit and vegetables as well as in cocoa. If it’s true that cocoa drinks (not chocolate, as the headline states, but cocoa drinks) improve ones ability to do maths and if it’s true that it’s the flavanols that are responsible for the stated beneficial effects of the cocoa on the human brain, then surely it would have been equally correct to state that “vegetables can help improve your maths”. [To be fair to the authors of the conference paper, they do recommend the consumption of plenty of fruit and veg.] Why headline the piece “How eating chocolate can help improve your maths”? Probably because we love to be told something that runs contrary to typical advice on diet – especially when it’s something that allows us to indulge ourselves ‘guilt-free’. [The same is true of the reporting of the health benefits of red wine, I think – try googling resveratrol and red wine for an idea of the media’s over-extrapolation of studies into a specific component of red wine that also appears in other foodstuffs.]
Of course, I can’t see the research on which the Telegraph report is based because at the moment it’s a conference presentation rather than a publicly published, peer-reviewed research paper. It occurs to me, though, that 30 is rather a small number of participants for a study of this nature. It also occurs to me that, given the flavanols were provided in the form of a cocoa drink, that there could be other ingredients in the cocoa that may have had effects on the brain. Cocoa contains methylxanthines, including a certain amount of caffeine.
In a paper on the effects of energy drinks on cognitive performance, the authors stated that “The findings suggest that most of the effects of energy drinks on cognitive performance are related mainly to the presence of caffeine” [PMID: 18470842], while in this paper [PMID: 12204388] on the effects of caffeine on human behavior, it is noted that:
[*]Caffeine increases alertness and reduces fatigue; Caffeine improves performance on vigilance tasks and simple tasks that require sustained response; [#]Effects on more complex tasks are difficult to assess and probably involve interactions between the caffeine and other variables which increase alertness; Regular caffeine usage appears to be beneficial, with higher users having better mental functioning.
Given the overlap between what the research says on the effects of caffeine on mental performance and what the authors of the conference presentation found, I’d be very interested to find what sort of control (if any) was used in the research on flavanol-rich cocoa drinks (I reiterate: not chocolate, but flavanol-rich cocoa drinks).
[*]Note that caffeine is said to increase alertness in the paper by A Smith, and in the report of the (caffeine-containing) cocoa drink with flavanol.
[#]Note that the effects of caffeine are said to be more difficult to assess with regards more complex tasks. Compare this with the report of the (caffeine-containing) cocoa drink.
Linky to the Telegraph report.