An ongoing study by Japans National Institute for Longevity into the links between human intelligence and what we eat and drink has found that the effects of alcohol on the middle aged and the elderly was that the average IQ of men who drink wine (grapes or rice) was 3.3 points higher than that of men who did not drink. Similarly, the IQ of women drinkers was 2.5 points higher than their teetotal sisters.

Subjects for the study shared the same income and educational level - roughly £50,000 a year and all were university graduates. The tests measured general knowledge (questions included naming the capital of Peru (Lima) and Japans first post-war Prime Minister (Naruhiko Higashikuni)). The powers of judgement and concentration in drinkers and non-drinkers over 40 were measured; while wine drinkers appeared to be brighter, the same was not true for drinkers of shochu (a local gin) and whisky. Head of Epidemiology research, Hiroshi Shirnokata said, "The benefits of wine and sake (rice wine) in raising IQ could be due to substances they contain, polyphenols, which are believed to slow the ageing process". Moderation was shown to be important as those who drank more than 540 ml (a little over a pint) of sake or wine a day had a lower intelligence quotients. Japan has the best international age longevity records, at 76.7 for men and 83.2 years for women.