Some of the smartest people i know have the pickiest insane babies that practically malnourish themselves from birth despite every sound intervention. Stubborn infants. They don’t seem to be the worse for it long term.
In countries with universal conscription, there should be, buried away somewhere in the Ministry of War, decades of data on hat/helmet sizes. Granted, the correlation between IQ and external head size is quite low, but it would be interesting to know whether heads are getting bigger.
Also, did the introduction of Caesarean baby deliveries lead to more people with bigger heads?
What would be the theoretical reason that height has gone up dramatically in, say, South Korea since the 1950s, and so have scores on IQ tests, but not intelligence?
It's also not clear why height and intelligence should be connected environmentally. Generally, the connection between the two represents shared genes (e.g., https://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1003451). Because IUGR leads to a disconnect in losses (i.e., substantial losses to stature without corresponding losses to brains), I think that also sets a good precedent for it being possible for gains in stature and intellect to be disconnected too.
OK, so height tends to be driven by leg length which is more environmental than heredity. Height increases tend to correlate over time with raw IQ test score increases, but causation doesn't prove correlation! It could be instead that the reason height and IQ test raw scores tend to correlate is ...?
I think the life history theory proposed by Woodley is the most probable for the Flynn(and recent anti-flynn) effect , but how it integrates with test basis needs more research. It's plausible that heritability is just high for g and torso length but more moderate for leg length(causing a major increase in overall height but not intelligence). Whatever (environmental factors) leading to an increase in intelligence after removing test bias in some countries, could be cancelled out by a genotypic decline(especially in countries that gradually increased in income etc. like the US).
What are your thoughts on this study finding an impact of prenatal mercury exposure on IQ(it used structural equation modelling, two measures of prenatal exposure, and the results were similar at 7 and 14 years)?
Regarding supplementation of pregnant women, wouldn’t the demographics you’ve listed be those most likely to have the perfect diet for their bodies?
These are places where the people are eating food that their great-great-great grandparents adapted to draw anything they need from. I haven’t actually looked at any of the studies, but it seems on the surface that to answer the question of whether we can improve the world’s average IQ through nutrition, a better study would be conducted on average Americans. The only problem to be solved then would be keeping all other variables constant.
No, there's no reason to believe that the global malnourished population is mismeasured due to adaptation to their traditional diets. Incidentally, people are not typically eating their traditional diets after their local markets globalize.
“People are not typically eating their traditional diets after their local markets globalize” is exactly my point.
Those eating a diet that draws from outside of their ancestral geographical origins (as typical Americans do, not to mention mixed-race individuals) that their bodies have historically never adapted to aren’t getting the right ratio of certain minerals/vitamins/etc (for example, any islanders who today don’t eat only what was found in their relatively small environment) Therefore, people in the MOST DEVELOPED countries nowadays may not be reaching the full cognitive potential passed down from their parents.
There is still no reason to believe that populations have adapted to only develop to their fullest with certain diets tailored at the population level.
I know you brought up the Lind / Krugman debate as a recommendation to do simple math to check if a claim is possibly true, but in that specific example I wonder whether the argument boils down to what Lind meant by “average”:
> Between 1977 and 1992, the average productivity of American workers increased by more than 30 percent, while the average real wage fell by 13 percent.
If he meant “mean,” then clearly Krugman is right. But if he meant “median,” then Lind could very well be right: the highly educated have seen their compensation increase a lot more in relative terms than workers at the bottom of the pay scale.
>instrumenting with local Imam opinions on fasting desirability and knowledge of the pregnancy exemption. Comparing outcomes for different Muslim groups based on their adherence levels could also be a viable way to get an answer and a replication
Could you explain how this would avoid the issue of confounding that you noted in the context of who fasts:
>The choice to fast was, evidently, selective. The choice to fast was related to obesity, being a mother who had never held a job, being less educated, and being in a consanguineous (inbred) marriage
If there's selection in choice to fast in particular, why wouldn't there be selection in adherence levels in general, or even in local imams, with imams moving to particular communities selectively, and potentially people moving between communities, selectively?
There could be problems with this method; no one said it was perfect, it's just an idea. If there's selection with respect to locale (which is sticky enough that it's probably not a big problem), then use changes in local Imams and assume (as with the Judge IV design) that they have sticky views.
You could check out the research on Japan and South Korea that showed a postwar IQ increase of up to 7.7 points per decade, correlated with the increase in height.
Those regions interestingly have iodine consumption an order of magnitude higher than the WHO’s recommendations and initiatives involving iodine supplementation (which use pathetically low amounts as far as I have seen).
Some of the smartest people i know have the pickiest insane babies that practically malnourish themselves from birth despite every sound intervention. Stubborn infants. They don’t seem to be the worse for it long term.
Also, down with most nutritional “science” lawl.
In countries with universal conscription, there should be, buried away somewhere in the Ministry of War, decades of data on hat/helmet sizes. Granted, the correlation between IQ and external head size is quite low, but it would be interesting to know whether heads are getting bigger.
Also, did the introduction of Caesarean baby deliveries lead to more people with bigger heads?
It would be great to test this with data from the Netherlands, Korea, Sweden, Norway, Denmark, Switzerland, and anyone else with the data!
Thanks.
What would be the theoretical reason that height has gone up dramatically in, say, South Korea since the 1950s, and so have scores on IQ tests, but not intelligence?
It's not at all clear to me!
It's also not clear why height and intelligence should be connected environmentally. Generally, the connection between the two represents shared genes (e.g., https://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1003451). Because IUGR leads to a disconnect in losses (i.e., substantial losses to stature without corresponding losses to brains), I think that also sets a good precedent for it being possible for gains in stature and intellect to be disconnected too.
I believe cremieux mentioned that height increases are primarily because of increases in leg length which are less heritable.
I believe that smoking in pregnancy effects femur length
OK, so height tends to be driven by leg length which is more environmental than heredity. Height increases tend to correlate over time with raw IQ test score increases, but causation doesn't prove correlation! It could be instead that the reason height and IQ test raw scores tend to correlate is ...?
I think the life history theory proposed by Woodley is the most probable for the Flynn(and recent anti-flynn) effect , but how it integrates with test basis needs more research. It's plausible that heritability is just high for g and torso length but more moderate for leg length(causing a major increase in overall height but not intelligence). Whatever (environmental factors) leading to an increase in intelligence after removing test bias in some countries, could be cancelled out by a genotypic decline(especially in countries that gradually increased in income etc. like the US).
What are your thoughts on this study finding an impact of prenatal mercury exposure on IQ(it used structural equation modelling, two measures of prenatal exposure, and the results were similar at 7 and 14 years)?
https://pubmed.ncbi.nlm.nih.gov/17067778/
That research is cited in a later review: https://link.springer.com/article/10.1007/s40806-017-0131-7
There was seasonal variation in IQ of sugarcane farmer in India post harvest and pre harvest which changes their poverty level.
https://lchc.ucsd.edu/MCA/Mail/xmcamail.2013_11.dir/pdfZG9oBsF_YC.pdf
No, there wasn't.
https://www.science.org/doi/10.1126/science.1246680
Regarding supplementation of pregnant women, wouldn’t the demographics you’ve listed be those most likely to have the perfect diet for their bodies?
These are places where the people are eating food that their great-great-great grandparents adapted to draw anything they need from. I haven’t actually looked at any of the studies, but it seems on the surface that to answer the question of whether we can improve the world’s average IQ through nutrition, a better study would be conducted on average Americans. The only problem to be solved then would be keeping all other variables constant.
No, there's no reason to believe that the global malnourished population is mismeasured due to adaptation to their traditional diets. Incidentally, people are not typically eating their traditional diets after their local markets globalize.
“People are not typically eating their traditional diets after their local markets globalize” is exactly my point.
Those eating a diet that draws from outside of their ancestral geographical origins (as typical Americans do, not to mention mixed-race individuals) that their bodies have historically never adapted to aren’t getting the right ratio of certain minerals/vitamins/etc (for example, any islanders who today don’t eat only what was found in their relatively small environment) Therefore, people in the MOST DEVELOPED countries nowadays may not be reaching the full cognitive potential passed down from their parents.
There is still no reason to believe that populations have adapted to only develop to their fullest with certain diets tailored at the population level.
I know you brought up the Lind / Krugman debate as a recommendation to do simple math to check if a claim is possibly true, but in that specific example I wonder whether the argument boils down to what Lind meant by “average”:
> Between 1977 and 1992, the average productivity of American workers increased by more than 30 percent, while the average real wage fell by 13 percent.
If he meant “mean,” then clearly Krugman is right. But if he meant “median,” then Lind could very well be right: the highly educated have seen their compensation increase a lot more in relative terms than workers at the bottom of the pay scale.
>instrumenting with local Imam opinions on fasting desirability and knowledge of the pregnancy exemption. Comparing outcomes for different Muslim groups based on their adherence levels could also be a viable way to get an answer and a replication
Could you explain how this would avoid the issue of confounding that you noted in the context of who fasts:
>The choice to fast was, evidently, selective. The choice to fast was related to obesity, being a mother who had never held a job, being less educated, and being in a consanguineous (inbred) marriage
If there's selection in choice to fast in particular, why wouldn't there be selection in adherence levels in general, or even in local imams, with imams moving to particular communities selectively, and potentially people moving between communities, selectively?
There could be problems with this method; no one said it was perfect, it's just an idea. If there's selection with respect to locale (which is sticky enough that it's probably not a big problem), then use changes in local Imams and assume (as with the Judge IV design) that they have sticky views.
My guess is that Charles Dickens wouldn't have noticed the Flynn Effect if he'd lived to be 150, but Charles Babbage would have:
https://www.unz.com/isteve/the-flynn-effect-across-time-and-space/
Autistics show a similar discrepancy between tests, which might support that the Flynn effect is due to mercury air pollution.
https://www.researchgate.net/publication/273789709_Rising-falling_mercury_pollution_causing_the_rising-falling_IQ_of_the_Lynn-Flynn_effect_as_predicted_by_the_antiinnatia_theory_of_autism_and_IQ
You could check out the research on Japan and South Korea that showed a postwar IQ increase of up to 7.7 points per decade, correlated with the increase in height.
Those regions interestingly have iodine consumption an order of magnitude higher than the WHO’s recommendations and initiatives involving iodine supplementation (which use pathetically low amounts as far as I have seen).
Indeed, Shohei Ohtani looks better fed than Japanese soldiers in 1941.