A study published in the NEJM last month(1) seems to show a pretty convincing positive trend that those countries who consume more chocolate per capita also receive more Nobel Prizes.
The author of the study, Dr. Franz Messerli, continues to associate this trend with one of the key active ingredients in chocolate (flavonol’s). Flavonol’s have previously been implicated in increased brain performance and brain related anti-ageing effects. OK so I’m willing to accept these points are loosely connected (maybe I just want to eat more chocolate…) but are there any problems with the method?
Having looked at the study there are a few surprising issues. First off, Wikipedia is used as a reference for the number of Nobel Laureates per capita in each country. Wikipedia is great for casual use, but it is famously unreliable for scientific use due to it’s open-source nature. That’s a big no-no straight away (especially when records of Nobel Laureates are pretty much open-access).
Anything else? Well it could be said that the data shows a large bias to European countries. Approximately half of all countries containing Nobel Laureates are not European. Yet in a study which compares only 23 (of 71) countries, only six are non-European. Couple this with the idea that Dr. Messerli’s chocolate eating records come from three European organisations and you get the idea that adding other non-European countries may skew the results against his hypothesis. What could be seen as even worse is the omission of the top three countries for Nobel Laureates per capita, two of which are European!
That said Dr. Messerli does criticise his own data thoroughly, mentioning that correlation may not = causation. His theories concerning plausible causation’s are also fairly amusing, including the flavonol argument above and the idea that Scientists from certain countries may be particularly sensitive to these chemicals (late night chocolate binge?).
In the end the paper isn’t really all that trustworthy. But to credit Dr. Messerli, I’m pretty sure he’s taking the piss and therefore probably didn’t put a whole lot of time into this project. So what are Dr. Messerli’s lasting recommendations? Dark Lindt chocolate apparently. Although he has yet to win a Nobel Prize himself.
To accentuate the actual point of this post: This is a classical example of why you should always critically analyse a paper instead of just taking it at face value. And leads me on to a topic I’m going to try and cover in my pages. Hopefully they will pop up some time soon!