March 03, 2015

Nutrition and IQ

One of the oldest claims about low IQ by Leftists is that it's all due to poverty.  Sound familiar?  More specifically, they say that low IQ just reflects poor nutrition.  Considering that African Americans are on the whole even more overweight than Caucasian Americans, that rather clearly flies in the face of the facts.  African Americans are on average 15 points behind white Americans but they aren't going hungry.

And in any case, if it were all due to nutrition, feeding up the children of poor people should make them all into Einsteins, should it not?  There is no known example of anything like that being achieved, however.

Aha!  But it's not the quantity alone that matters. It's quality too.  People need to eat "healthily" rather than eat more. And the prime candidate for a "healthy" diet is the Mediterranean diet.  We all know that, don't we? If we all ate like the Greeks with plenty of vegetables, plenty of garlic and plenty of olive oil we would be so much healthier -- and slimmer to boot.  The main reason the Mediterranean diet is lauded is that accords with Ancel Keys' famous demonstration that red meat it bad for you (high red meat consumption is correlated with shorter lifespan).

Pesky fact: Keys only looked at death from cardiovascular events (heart attacks and strokes).  He did not look at overall mortality.  When you include all causes of death in the correlation, the correlation with red meat consumption vanishes.

Pesky fact: The traditional Australian diet (beef, beef and more beef in various forms) is about as opposite to the Mediterranean diet as you can imagine yet Australians live longer than any people of any Mediterranean nation -- so scrub the Mediterranean diet idea once and for all.

Another pesky fact:  Eskimos eating a traditional diet eat little else than meat and blubber.  It's hard to grow vegetables near the North Pole.  Yet at any age point, Eskimos have LESS cardiovascular disease than  we do.

So: There may be such a thing as a healthy diet but nobody so far has been able to track it down convincingly.  Maybe some day somebody will find a magic vegetable that will make blacks as smart as whites but I wouldn't hold my breath.

Funnily enough, however, there is a SMALL element of truth in what Leftists say. In very nutritionally deprived people -- such as Africans whose dietary staple is  "Mealie-pap" (corn-porridge) -- adding micronutrients (vitamins and minerals) to the diet of their children does bring about an IQ gain -- but only of about 5 points.  On better nourished people, there is no such gain, however.

Some reinforcement of that story can be found here.  The amount of red meat eaten by different nations is tabulated.  And amount of red meat is a pretty good proxy for a high quality food supply generally.

And we find, of course, that the nations of Africa all have a low per capita meat consumption.  They are too poor for anything else.  And they are also nations that show very low IQs, as tabulated by Lynn and VanHanen.  Compared to Africans, African Americans (who are about 20% white genetically) are an intellectual elite.  So a largely vegetarian diet has not  helped Africans much.

But there are some black countries that do have a high meat consumption.  Saint Lucia in the Caribbean lives well off the back of American tourism so has one of the highest meat consumptions per capita (though not nearly as high as the New Zealanders with their seven tasty sheep per person). Yet the average IQ in St Lucia is an abysmal 62, very similar to what we see in Africa.

So vegetables are not the magic cure for low IQ in blacks nor is a rich  diet.  What else is there? Can we concede that diet is essentially irrelevant to IQ?






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