IQ in childhood and vegetarianism in adulthood: 1970 British cohort study
BMJ 2007; 334 doi: https://doi.org/10.1136/bmj.39030.675069.55 (Published 01 February 2007) Cite this as: BMJ 2007;334:245
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"To Enjoy Unique Experiences" Isn't this the true meaning of life? If
you are a person who can watch the same movie 20 times, either you're
lying to yourself that you enjoy it or you have a low IQ. It seems odd to
me that a person with a High IQ wouldn't eat meat. Lettuce gets boring.
They only make so many salad dressings. I believe that obsessing about
what you should eat may require a higher than average IQ since it requires
deeper thought and consideration. This, in my opinion, does not mean that
the vegetarian/IQ correlation is directly associated. The cause is
something else. Something you're not considering or something you're not
looking for. I would start by researching why a person is a vegetarian.
When did they decide to become a vegetarian and what was their motivation?
From my point of view it must be a behavioral dysfunction. All in all, if
you are a vegetarian, start thinking bigger. Why stop at the big picture
of vegetables when their are bigger problems to contemplate? For example,
aren't plants alive too? Why would you give more value to a bird and less
to a tree? Because a bird has a brain? Why should having a brain make you
more valuable? All life is equal, even as equal as inanimate matter.
Energy is energy and life is simply a more complex reaction of different
energies. Keep sharp, keep finding answers, don't sell yourself out to
hype and make your own answers for why you are doing what you are doing.
Competing interests:
None declared
Competing interests: No competing interests
One of the striking findings of this study is that 1/3 of those who
describe themselves as vegetarian in fact eat fish and chicken. Being a
vegetarian myself (that is, somebody who eats no meat) I am intrigued -
and I have to say often irritated - by this widespread phenomenon. Even
not very clever people must know that fish and fowl aren't vegetables, so
what is going on?
I suspect the answer is that vegetarianism is more widely recognized
as a desirable behaviour than its prevalence would suggest. However, like
cycling and not smoking in pubs it is harder to practice than it should
be, so people describe what they would like to be rather than what they
are. There is a lesson here for those who wish to improve the public
health.
Competing interests:
None declared
Competing interests: No competing interests
ACCORDING to just published work of Spencer et al[1], who studied
medical students in the Class of 2003 (n=1,849) at 15 US medical schools
(response rate 80%),……
“…….THE PREVALENCE of vegetarianism was higher among US medical
students than among other US adults, although the prevalence declined
during medical school……”
IF BEING a medical student might be taken as evidence of being of
above average intelligence in the first place, such that IQ confirmation
by testing is unnecessary, it is interesting to note the decline in
vegetarianism during medical school. This could suggest that medical
culture generally is anti rather than pro vegetarianism, since almost by
definition a “student” is moulded in certain directions by a “school”.
MY OWN HUNCH as to the finding[2] is that being in a dietary
minority[vegetarian] makes it difficult to survive, and being generally
more intelligent than the meat eaters, is an asset required to remain
vegetarian[and hence alive] at all.
[1]Spencer EH, Elon LK, Frank E. Personal and professional correlates
of US medical students' vegetarianism.J Am Diet Assoc. 2007 Jan;107(1):72-
8.
[2] Catharine R Gale, Ian J Deary, Ingrid Schoon, and G David Batty.
IQ in childhood and vegetarianism in adulthood: 1970 British cohort study
BMJ 2007; 334: 245
Competing interests:
Vegetarian
Competing interests: No competing interests
I read your article with interest!
I think the findings can be explained in a variety of ways as
suggested previously. Higher intelligence, means a push for a healthier
lifestyle. But perhaps also a deeper contemplation of the ethics of
killing animals for food?
Perhaps people with higher IQ's are more likely to contemplate on
spirituality, animal rights, world economics (it's more expensive to raise
a pig than grow crops)to make their life-style choices?
Competing interests:
None declared
Competing interests: No competing interests
As the authors already point out, the link between childhood IQ and
vegetarianism in later life [1] is perhaps not driven by a causal chain of
mechanisms related to health. We have some data supporting a different
point of view. As the frequency of vegetarians in the population is
extremely low (in their data only 4.5 %), vegetarianism could be
considered as a type of non-conformist behavior. We argue below that
acting in a non-conformist way is less threatening for highly than for
less intelligent people. Therefore, we predict a positive relationship
between non-conformist behavior and general intelligence. To give support
to our argument, we show another similar relationship between general
intelligence and another (more general) type of non-conformity, namely the
‘need for uniqueness’.
Non-conformist behavior may threaten the belongingness to a social
group, or has the potential of enlarging the psychological distance from
others. People who deviate from the group are more likely to be punished,
ridiculed, or even rejected by other group members [2]. In that light a
mechanism such as social pain (i.e. “the distressing experience arising
from the perception of actual or potential psychological distance from
close others or a social group.”[3]) that prevents someone from social
isolation situations appears as a functional characteristic. After all, in
human’s natural environment acquiring resources in isolation is more
difficult than in groups [4]. Prospects for isolated people are rather
grim. Therefore, the need to belong may reduce people’s inclination to act
in a non-conformist way, through the motivation to secure the acquisition
of resources. However, general intelligence is a strong predictor of
future resources [5, 6]. So, the more intelligent someone is, the less
dependent this person is on the group to acquire resources. This means
that highly intelligent people can afford more non-conformist behavior
because of their capacity to secure resources in isolation. Therefore, we
propose that as general intelligence increases the need to conform to
group norms decreases.
To test this hypothesis, we measured the ‘need for uniqueness’ [7]
and a raven progressive matrices measure of general intelligence [8]. The
need for uniqueness is measured by a scale with statements all indicating
a low level of conformity (e.g. “I often dress unconventionally even when
it’s likely to offend others.” and “When a style of clothing I own becomes
too commonplace, I usually quit wearing it.”). Our study (32 men, 14
women) showed a significant positive relationship between the need for
uniqueness and general intelligence (r = .35, p = .017). This relationship
was similar for both men (r = .32) and women (r = .46).
Summarized, we explain the IQ-vegeterianism findings from a
psychological point of view and show converging evidence. Moreover, we
generalize these findings to a positive relationship between general
intelligence and non-conformity in general. Our data give support to this
view as a more general type of non-conformist behavior than vegetarianism
(the need for uniqueness) is similarly related to general intelligence.
[1] Gale CR, Deary IJ, Schoon I, & Batty, D. IQ in childhood and
vegetarianism in adulthood: 1970 British cohort study. BMJ
2006;doi:10.1136/bmj.39030.675069.55
[2] Griskevicius V, Goldstein NJ, Mortensen CR, Cialdini RB, Kenrick
DT. Going along vs. going alone: when fundamental motives facilitate
strategic (non)conformity. J Pers Soc Psych 2006;91: 281-294.
[3] Eisenberger NI, Lieberman MD. Why rejection hurts: a comon neural
alarm system for physical and social pain. Trends in Cognitive Sciences
2004;8: 294-300.
[4] Baumeister RF, Leary ML. The need to belong: Desire for
interpersonal attachments as a fundamental human motivation. Psychol Bull
1995; 117: 497-529.
[5] Gottfredson LS. Intelligence: Is it the epidemiologists’ elusive
“fundamental cause” of social class inequalities in health? J Pers Soc
Psych 2004; 86: 174-199.
[6] Kanazawa S. Why beautiful people are more intelligent.
Intelligence 2004; 32: 227-243.
[7] Tian KT, McKenzie K. The long-term predictive validity of the
consumers' need for uniqueness scale. Journal of Consumer Psychology 2001;
10: 171-193.
[8] Millet K, Dewitte S. Altruistic behavior as a costly signal of
general intelligence. Journal of Research in Personality in press.
Competing interests:
None declared
Competing interests: No competing interests
Did Rameet S Uberoi even read the title of the paper before writing a
response? The article is not suggesting a causal link from vegetarianism
to intelligence, and says nothing about what happens to vegetarians - the
result would not be inconsistent with vegetarianism leading to a 5 point
drop in IQ.
Competing interests:
None declared
Competing interests: No competing interests
I once viewed a comparitive MRI cross-section of a vegetarian and a
meat-and-potato-fast-food diets. The vegetarian cross section showed open
vessels and lean muscle mass while the non-vegetarian demonstrated fat-
marbled muscle mass and associated fatty-lined vessels. Circulation of
blood appears to be necessary for growth progress of intelligence peak.
Intelligence potential is directly correlated with healthy blood
circulation inversely related to chronic dietary protocols associated with
high-normal blood pressure, and are inversely related to stroke and
ischemic heart disease. The vegetarian diet appears to generate blood
circulatory health that may permit intelligence quotient to reach maximum
potential.
Ophir et al. (1983) concluded that the protective antihypertensive
factor in the vegetarian diet is the presence of high amounts of
potassium. Ninety-eight (98) confirmed adult vegetarians were examined
against a matched group of nonvegetarians living in the same urban
environment in order to evaluate the prevalence of arterial hypertension.
The average blood pressure was 126/77 for the vegetarians and 147/88 for
the control group (p less than 0.05). Significantly lower blood pressure
was found in every decade of age. Only 2% of the vegetarians had
hypertension (higher than 160/95) as compared to 26% hypertensives in the
nonvegetarians. These differences in blood pressure were maintained also
when individuals with the same "relative weight" were compared. Family
history of hypertension was similar in both groups.
Joshipura (1999) examined the dietary habits of 75,596 women aged 34
through to 59 for 14 years and 38,683 men aged 40 through to 75 for nine
years. Eating five to six servings of fruit (or vegetables) daily was
found to lower the risk of stroke risk by 30% in middle-aged people.
Subjects who consumed five to six daily servings of fruit or vegetables
had 30% less chance of experiencing a stroke compared to those who ate two
and a half to three servings a day. Eating more than six daily servings
provided no additional protection, but eating just one extra serving of
fruit or vegetables daily reduced stroke risk by 6 percent. Cruciferous
vegetables, green leafy vegetables and citrus juice provided the most
protection.
Ovesen (2005) associates an increased intake of about 800 g per day
vegetables (and fruit) with a 20% reduced risk of developing ischemic
heart disease and concluded that an increased intake of a mix of fruits
and vegetable reduces the risk of IHD.
The MRI cross section reference may therefore present a dramatic
"picture" of how diet choices effect blood circulation and the potential
gain of or deterioration in the progress for realizing optimal
intelligence quotient.
References
Ophir, O., et al. Low blood pressure in vegetarians: The possible
role of potassium. American Journal of Clinical Nutrition 37(5):755-762,
1983.
Joshipura K. Journal of the American Medical Association.
292(13):1233-1239, 1999.
Ovesen LF. [Increased consumption of fruits and vegetables reduces
the risk of ischemic heart disease.] Ugeskr Laeger. 167(25-31):2742-2747,
2005.
Bill Misner, Ph.D.
AAMA Board Certified Alternative Medicine Practitioner
Competing interests:
None declared
Competing interests: No competing interests
I was vegetarian, vegan to be exact, which means no consumption of
cheese or milk, or any animal derivated products, from when I was 20 till I was
33, and I am not from a high social class.
Both my parents were workers, and my mum had to leave school at the age of 14 to go
to work.
I am from a classic worker family with a large number of
children and parents with a very low education level, though my mum read
a lot of books.
I have studied at university and obtained a diploma in a large variety of
matters, like electronic engineer, philosophy, master
in project leadership, team building and teaching, translator, etc...
I don't know if this confirms or informs your research: I am the only one
in the family who has studied at university and the only one to
be vegetarian.
I stopped gradually being a vegetarian due to external pressure in my
close environment, but I still consider vegetarianism to be a
preferred/highly recommendable way of life or way to feed oneself, compared
to meat eater.
I see meat eating as a form of cannibalism, a killing of other species in an unecessary/unmotivated assassination.
It is basically wrong as well as ethically uncorrect. Not just logically but
ethically, and that's how I view it.
Does high IQ have an influence on a person's mentality and therefore ethical sense, so you have the answer as to how high IQ relates to vegetarianism.
As a child, I already began to view it as incorrect.
It is an instinctive reaction to the concept of killing, even if the words
peace and love and instinct rarely sing together.
I hope this contributes to your research.
Competing interests:
None declared
Competing interests: No competing interests
It is obviously a characteristic of those with a high IQ in my case
148 and vegetarian for 26 years, that diet becomes a subject of abiding
interest.
Consequently food choices that avoid cruelty to animals and fish are
undertaken as obvious. Diets that minimise harm to the individual human
and in fact bolster the bodies defences are also obvious to vegetarians.
Bigger brain vegetarian food longer life less disease seems obvious to
me.
David
Competing interests:
None declared
Competing interests: No competing interests
Re:To Enjoy Unique Experiences
Aaron, you seem to view quite a narrow picture yourself. Firstly,
there's more for a vegetarian to eat than lettuce. Did you ever explore
all vegetables, fruits, seeds etc. and how many combinations they can
make? Even meat eaters don't normally have THAT many different kinds of
meat. I'm a vegetarian and I don't even eat salads, lettuce is mostly
water and I need food that fill me up. Since I decided to stop eating meat
I've both been healthier and started enjoying food more.
Secondly, there's more than one reason to be a vegetarian... I didn't
become one for the sake of the animals, even if that's a bonus. I do it
for the environment. The meat industry creates huge emissions of
greenhouse gases and exchanging a meal with meat with a vegetarian cuts
it's environmental "costs" by half. Imagine what a great difference it
could be if everyone had at least one or two vegetarian meals a week! In
the beginning I had meat a bit now and then since I still like the taste,
can't see why everyone have to be either meat eating or vegetarian/vegan.
Now I've decided to stop eating meat completely with exeptions for fish
(caught where the stocks are not over fished). I can't see why chosing
food logically and respecting the environment and the animals would mean
that you're less intelligent?
Competing interests: No competing interests