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The n e w e ng l a n d j o u r na l of m e dic i n e

o c c a siona l no t e s

Chocolate Consumption, Cognitive Function,

and Nobel Laureates
Franz H. Messerli, M.D.

Dietary flavonoids, abundant in plant-based foods, cause the population of a country is substantially
have been shown to improve cognitive function. higher than its number of Nobel laureates, the
Specifically, a reduction in the risk of dementia, numbers had to be multiplied by 10 million.
enhanced performance on some cognitive tests, Thus, the numbers must be read as the number
and improved cognitive function in elderly patients of Nobel laureates for every 10 million persons
with mild impairment have been associated with in a given country.
a regular intake of flavonoids.1,2 A subclass of All Nobel Prizes that were awarded through
flavonoids called flavanols, which are widely October 10, 2011, were included. Data on per
present in cocoa, green tea, red wine, and some capita yearly chocolate consumption in 22
fruits, seems to be effective in slowing down or countries was obtained from Chocosuisse
even reversing the reductions in cognitive per- (,
formance that occur with aging. Dietary flavanols Theobroma-cacao (
have also been shown to improve endothelial wissen/wirtschaft/international/konsum), and
function and to lower blood pressure by causing Caobisco (
vasodilation in the peripheral vasculature and in Data were available from 2011 for 1 country
the brain.3,4 Improved cognitive performance (Switzerland), from 2010 for 15 countries, from
with the administration of a cocoa polyphenolic 2004 for 5 countries, and from 2002 for 1 coun-
extract has even been reported in aged Wistar try (China).
Unilever rats.5
Since chocolate consumption could hypotheti- Re sult s
cally improve cognitive function not only in indi-
viduals but also in whole populations, I won- There was a close, significant linear correlation
dered whether there would be a correlation (r=0.791, P<0.0001) between chocolate con-
between a countrys level of chocolate consump- sumption per capita and the number of Nobel
tion and its populations cognitive function. To laureates per 10 million persons in a total of 23
my knowledge, no data on overall national cog- countries (Fig. 1). When recalculated with the
nitive function are publicly available. Conceiv- exclusion of Sweden, the correlation coefficient
ably, however, the total number of Nobel laure- increased to 0.862. Switzerland was the top per-
ates per capita could serve as a surrogate end former in terms of both the number of Nobel
point reflecting the proportion with superior laureates and chocolate consumption. The slope
cognitive function and thereby give us some of the regression line allows us to estimate that
measure of the overall cognitive function of a it would take about 0.4 kg of chocolate per capita
given country. per year to increase the number of Nobel laure-
ates in a given country by 1. For the United States,
Me thods that would amount to 125 million kg per year.
The minimally effective chocolate dose seems to
A list of countries ranked in terms of Nobel hover around 2 kg per year, and the doseresponse
laureates per capita was downloaded from curve reveals no apparent ceiling on the number
Wikipedia ( of Nobel laureates at the highest chocolate-dose
countries_by_Nobel_laureates_per_capita). Be- level of 11 kg per year.

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P<0.0001 Denmark
Nobel Laureates per 10 Million Population


United Kingdom


United Ireland Germany

The Netherlands States
10 France
Canada Finland

5 Poland Australia
Portugal Greece
0 Japan
China Brazil

0 5 10 15
Chocolate Consumption (kg/yr/capita)

Figure 1. Correlation between Countries Annual Per Capita Chocolate Consumption and the Number of Nobel
Laureates per 10 Million Population.

Discussion about 14 Nobel laureates, yet we observe 32.

Considering that in this instance the observed
The principal finding of this study is a surpris- number exceeds the expected number by a fac-
ingly powerful correlation between chocolate tor of more than 2, one cannot quite escape the
intake per capita and the number of Nobel laure- notion that either the Nobel Committee in
ates in various countries. Of course, a correla- Stockholm has some inherent patriotic bias
tion between X and Y does not prove causation when assessing the candidates for these awards
but indicates that either X influences Y, Y influ- or, perhaps, that the Swedes are particularly
ences X, or X and Y are influenced by a common sensitive to chocolate, and even minuscule
underlying mechanism. However, since choco- amounts greatly enhance their cognition.
late consumption has been documented to im- A second hypothesis, reverse causation
prove cognitive function, it seems most likely that is, that enhanced cognitive performance
that in a dose-dependent way, chocolate intake could stimulate countrywide chocolate con-
provides the abundant fertile ground needed for sumption must also be considered. It is con-
the sprouting of Nobel laureates. Obviously, ceivable that persons with superior cognitive
these findings are hypothesis-generating only function (i.e., the cognoscenti) are more aware
and will have to be tested in a prospective, ran- of the health benefits of the flavanols in dark
domized trial. chocolate and are therefore prone to increasing
The only possible outlier in Figure 1 seems to their consumption. That receiving the Nobel
be Sweden. Given its per capita chocolate con- Prize would in itself increase chocolate intake
sumption of 6.4 kg per year, we would predict countrywide seems unlikely, although perhaps
that Sweden should have produced a total of celebratory events associated with this unique

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occasional notes

honor may trigger a widespread but most likely Nobel Prize, and it closely correlates with the
transient increase. number of Nobel laureates in each country. It
Finally, as to a third hypothesis, it is diffi- remains to be determined whether the consump-
cult to identify a plausible common denomina- tion of chocolate is the underlying mechanism
tor that could possibly drive both chocolate con- for the observed association with improved cog-
sumption and the number of Nobel laureates nitive function.
over many years. Differences in socioeconomic
Dr. Messerli reports regular daily chocolate consumption,
status from country to country and geographic mostly but not exclusively in the form of Lindts dark varieties.
and climatic factors may play some role, but Disclosure forms provided by the author are available with the
they fall short of fully explaining the close cor- full text of this article at
relation observed. From St. LukesRoosevelt Hospital and Columbia University,
New York.
S t udy Limitations This article was published on October 10, 2012, at

The present data are based on country averages, 1. Nurk E, Refsum H, Drevon CA, et al. Intake of flavonoid-rich
and the specific chocolate intake of individual wine, tea, and chocolate by elderly men and women is associated
with better cognitive test performance. J Nutr 2009;139:120-7.
Nobel laureates of the past and present remains 2. Desideri G, Kwik-Uribe C, Grassi D, et al. Benefits in cogni-
unknown. The cumulative dose of chocolate that tive function, blood pressure, and insulin resistance through
is needed to sufficiently increase the odds of be- cocoa flavanol consumption in elderly subjects with mild cogni-
tive impairment: the Cocoa, Cognition, and Aging (CoCoA)
ing asked to travel to Stockholm is uncertain. Study. Hypertension 2012;60:794-801.
This research is evolving, since both the number 3. Corti R, Flammer AJ, Hollenberg NK, Lscher TF. Cocoa and
of Nobel laureates and chocolate consumption cardiovascular health. Circulation 2009;119:1433-41.
4. Sorond FA, Lipsitz LA, Hollenberg NK, Fisher ND. Cerebral
are time-dependent variables and change from blood flow response to flavanol-rich cocoa in healthy elderly
year to year. humans. Neuropsychiatr Dis Treat 2008;4:433-40.
5. Bisson JF, Nejdi A, Rozan P, Hidalgo S, Lalonde R, Mess-
aoudi M. Effects of long-term administration of a cocoa poly-
Conclusions phenolic extract (Acticoa powder) on cognitive performances in
aged rats. Br J Nutr 2008;100:94-101.
Chocolate consumption enhances cognitive func- DOI: 10.1056/NEJMon1211064
tion, which is a sine qua non for winning the Copyright 2012 Massachusetts Medical Society.

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