Sunday, April 18, 2004


I am rather surprised that the story about some Europeans being taller than Americans has attracted such a lot of attention without anyone (as far as I can see) tumbling to what the finding really shows. Even the careful Iain Murray missed it. The finding, in brief, was that the average American height has stopped increasing but average heights in some European countries have not. And some Europeans -- such as the Dutch -- are much taller than Americans on average. The data underlying the finding may not be all that sound but let us assume that they are:

Anti-American commentators have linked the finding to nutrition -- saying that it shows Americans to be poorly nourished. Given the "obesity epidemic" in America, that is a pretty hilarious explanation but it does contain the grain of truth that there is some connection between nutrition and height. As the geneticists (such as Eaves et al., 1999) have shown, final height is a product of genetic potential plus environmental influences -- and nutrition is undoubtedly one of those environmental influences. Putting it another way, your full genetic potential is realized only when the environmental conditions are ideal. So what the data really show is that ONLY IN AMERICA have the ideal environmental conditions for height maximization been realized. That is why Americans have stopped growing. America ALREADY has gained all it can from nutrition etc. The fact that European heights are still growing shows, then, that they still do not have ideal conditions there for realizing their maximum height. They are still catching up. In short, the data show exactly the opposite to what has been claimed: It is Europeans who are lacking in something that influences height. The traditional European habit of consuming fruit and vegetables in preserved and pickled form rather than in fresh form may be the nutritional factor involved.

An immediate objection to my account is of course the fact that SOME Europeans are much taller than Americans on average. How can they be so tall if they have bad nutrition (or whatever else has been holding them back)? Once again the answer is to be found in the Eaves et al (1999) study: The MAIN influence on height is genetics so if coastal North Western Europeans (such as the Dutch and the Scandinavians) have good genetics for height they will still be taller on average even if their nutrition is not ideal. And that coastal North-Western Europeans tend to be very tall has been known at least since the Viking age. Why they have long been among the world's tallest people (along with some very dubiously nourished East Africans) nobody knows for sure but only a small percentage of the American population is of coastal North Western European ancestry so the final American average must be much lower. And the fact that the legionaries of the ancient Roman empire were real shorties suggests that average national height is a very minor factor (if it is a factor at all) in national achievement and felicity.

Eaves, L.J., Martin, N.G., Meyer, J.M. & Corey, L.A. (1999) "Biological and cultural inheritance of stature and attitudes". In: Cloninger, C.R., Personality and psychopathology. Washington, D.C.: American Psychiatric Press.


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