Vegetarians More Intelligent: study

http://www.chinadaily.com.cn/lifestyle/2006-12/15/content_759815.htm

[quote]A study of thousands of men and women revealed that those who stick to a vegetarian diet have IQs that are around five points higher than those who regularly eat meat.

Writing in the British Medical Journal, the researchers say it isn’t clear why veggies are brainier - but admit the fruit and veg-rich vegetarian diet could somehow boost brain power.[/quote]

[quote]
However, vegans - vegetarians who also avoid dairy products - scored significantly lower, averaging an IQ score of 95 at the age of 10.[/quote]

For any meat-eaters wanting to understand the article:

children’s picture dictionary

:smiley:

Gee five whole points? Gosh then I wouldn’t be able to remember how the British discovered Uranus. :raspberry:

I eat meat and I’m pretty fucking brainy.

Isn’t Sean Vegan??

Yeah! Me too!

Now where’s the report about how much smellier veggies are?

No, I’m not. And well done for getting a two-syllable word in! :wink:

Not knowing the 11-times-table all the way through or having constant cabbage-farts? No contest. Man, I’m GLAD I’m dumb. (If I were dumb, which I’m not since I’m a fucking brainiac. But if I were. Cabbage-farts.)

So, yeah.

No-one says you have to choose.

You can’t fool mother nature:
Which animals are smarter, the carnivores or the herbivores?

Veggies are lazy; plants can’t run away.

the fact that there is a correlation proves nothing about the cause or which is dependent on the other, if at all. the study is fairly flawed in its selection of candidates, and if i were the editor at that journal, i would not have allowed the srticle to get published in the first place.

the most probable explanation, and admitted as such by one of the authors, is that the vegetarians come from better educated families, where they are allowed to express their opinions more. actually having an opinion on something can be a sign of more intelligence, so those adopting vegetarianism are selected from a more intelligent stock to begin with. ergo, experimental conclusion is invalid right out of the box.

there is no link between intelligence and vegetarian diet. there is a link between diet and cancer, etc. between diet and obesity. between diet and poverty. and many more. but vegetarianism, no. humans are not meant to be vegetarians anyway. they are omnivores, like all other apes, and bears and pigs. just that most people these days eat too much proitein: you don’t need to eat more than a small handful of meat or termites or a lizard each day.

vegans being less intelligent i can understand… they get far less or none of those essential oils that only come from animal foods, which are required for correct neuron membrane liquidity, and which allow you to make more and faster interconnections in the brain.

Shaw said, ‘A mind of the calibre of mine cannot drive its nutriment from cows’. so, he ate vegetables: thus equating himself with the humble potato and the beet instead. sheesh! and i used to think he was so cool.

Why are you so sure? I’m fairly sure it would be easy to proove that there is a link between intelligence and a healthy diet. From there it’s quite logical to suppose that vegetarians might (on average) eat healthier than meat-eaters, and therefore might be more intelligent. I don’t know if that’s the case or not, but you shouldn’t rule it out.

Meant to? That’s a meaningless statement.

I’m vegetarian, smart and smelly. (Well smelly anyway).

Brian

Excellent post, urodacus!

Anyone who has studied scientific methodology should be able to easily see how badly flawed this report was. As you say, it is a well known fact that correlations do not prove anything about causation. Only random assignment of subjects to experimental and control groups (where the only difference between the two is the diet) can hope to say anything about diet causing intelligence. All this report really shows is that more intelligent kids (perhaps due to the culture they’re in, perhaps due to a better education, who knows?) are more likely to make the choice to be veggies later. It shows ZIP NADA NOTHING about what diet does to intelligence.

Furthermore, the results are not presented in enough detail (including significance levels – kinda like margins of error in polls, for the unitiated) for the reader to determine whether the study has any validity WHATSOEVER.

Yes, it would be, in theory, but this requires a scientific experiment, not sloppy gathering of the usual and widely misunderstood correlational data. However, with an adequate sample size and given a healthy diet for both the experimental vegetarian group and the omnivorous control group, which must be randomly assigned, btw, not chosen for their pre-existing diet, I’ll bet you Stray Dog’s testicles that there will be no statistically significant difference in resulting intelligence.

Humans share a common trait with other primates: non-specialized dentition. As a group, our teeth suggest that we are opportunistic eaters, equally adapted to veggies or flesh.

Isn’t the flaw in one’s own interpretation of the study (or, actually, the article)? It states that vegetarians are more intelligent; it doesn’t state that being vegetarian makes people more intelligent.

It actually details how intelligent kids become vegetarians, though the researchers, obviously in response to a question, “admit the fruit and veg-rich vegetarian diet could somehow boost brain power.”

If you guys didn’t eat so much meat, you would have spotted that. :smiley: :wink:

And humans are “meant to” procreate once we’re fertile. So I guess that means you approve of lowering the age of consent from 18/16/whatever to when girls begin menstruating, which nowadays is around 12 or 13 years old.

I think we’re ‘meant to be’ primarily vegetarian, like our closest relative, the chimpanzee.

It’s a shame the article didn’t show any stats for those people who only have the occasional kill.

[quote=“Stray Dog”]Isn’t the flaw in one’s own interpretation of the study (or, actually, the article)? It states that vegetarians are more intelligent; it doesn’t state that being vegetarian makes people more intelligent.
[/quote]

You’re right. These statements from the news report are not accurate:

  1. “…with research showing vegetarians are more intelligent than their meat-eating friends.” The study did not address the current intelligence of participants, just their intelligence when they were 10. It was a birth cohort study that began in 1970.

  2. “A study of thousands of men and women revealed that those who stick to a vegetarian diet have IQs that are around five points higher than those who regularly eat meat.” “Have” is clearly the wrong word as, again, current intelligence was not assessed.

The main study question was “Does a higher IQ make this decision [to become a vegetarian] more likely?”

A couple other things worth mentioning:

They did report statistical significance for that 5-point difference and also did some other statistical analyses to account for the effects of sex, social and economic status, etc. The association of IQ with diet remained statistically significant, though it was diminished to a certain extent.

Vegans, or, as the report described them, those who went whole hog, actually had lower childhood IQ scores.

And I still don’t see how you can call yourself a vegetarian if you eat chicken or fish. So there.

Here’s the URL for the full article: bmj.com/cgi/rapidpdf/bmj.39030.675069.55v1

Humans share a common trait with other primates: non-specialized dentition. As a group, our teeth suggest that we are opportunistic eaters, equally adapted to veggies or flesh.[/quote]

humans also have a generalist gut: not quite as short or with the same kind of duodenum or ileum as obligate carnivores like cats, and nothing like the long gut with multiple specialisation for digestion of herbage like ruminants or other grazers like dugongs, cows, giraffes, etc… something in between these two extremes. we also have excellent ability to absorb fats in high doses, and to eat a large meal seldom, just like carnivores. and we have a gall bladder, unlike other generalists like rodents such as rats, to store bile (also known as gall, one of the traditional four humours*) so we can release enough of it at a single burst when we finally catch something good and fleshy to eat…

together with our forward pointing eyes, stereo vision, mixed cutting/crushing/grinding dentition, and several other features of omnivores and carnivores, we are designed for eating occasional large meals of meat. this is what i meant by “meant to eat meat”: we are designed to do it by our evolutionary history.

i am not anthropomorphising here. in a similar vein, my ducati is not meant to be ridden in city traffic, but i do that sometimes from neccesssity. it is meant to be run on full throttle through twisty mountain roads: it is designed to do it. the difference is the ducati designer is a human in bologna, not natural selection operating in the available design space of the primate lineage.

if you then make a conscious choice to refrain from eating meat, fine. you will not be as heathy or as energetic as you can be from getting the occassional meat meal. you probably will be more healthy than someone who eats too much meat… and besides, it’s expensive and time consuming to eat a vegie diet and get sufficient nutrition, especially if you have to harvest it all yourself.

there are those who claim that the human experiment really only got a kick start when we started to eat more meat, in particular termites and other insects, maybe some 2-3 million years ago. that is why our brains require essential fatty acids found in large amounts only in cooler bodied animals like fish and insects. and not found at all in the plant kingdom. so in reality we have both been designed to eat meat, and by eating meat. you will be doing youurself a great disserrvice to cut all animla protein out of your diet, all you vegans.

notice i did not say that we must eat a whole pig each time we sat down. that would be greedy. one must not be a pig oneself.

now, let’s argue about that study at another time. but briefly: flawed methodology and interpretations abound in science, it is just a pity seeing it published in BJM. human longitudinal studies are notoriously difficult to control and to select. a thousand people is not a large enough sample size, given the variables involved, and there were insufficient age-education-physique-social standing matches made, and i did not like their statistical analyses. this kind of criticism is actually my job, in another allied area of science.

*four humour body system from galen, after many greeks too: blood (sanguine), black bile (Melan choler), yellow bile or gall (Choler) and phlegm. hence, a phlegmatic person, a person of good humour, a sanguine atitude, melancholy, etc… a bit like the five elements in chinese system. unfortunately, it has not died out in weestern science yet, and still influences many naturopaths etc who think old ‘knowledge’ is better. see wiki article for summary:

en.wikipedia.org/wiki/Humours