A report on the relationship between poor nutrition and antisocial
behaviour
The present report aims to explore the effects diet may have on the development of antisocial
behaviour. A growing body of scientific evidence (East et al., 2018; Liu & Raine, 2006;
Robinson et al., 2018). suggests that externalizing behaviour problems may arise in part as a
consequence of nutritional inadequacies in susceptible individuals. Although different lines of
evidence seem to support a correlational relationship between malnutrition and antisocial
behaviour, as of yet, no actual, causal link has been firmly established. It is highly unlikely that
antisocial behaviour is solely caused by past or present nutritional deficiencies. However,
poor nutrition may exacerbate behaviour problems.
Nutritional deficiencies and antisocial behaviour
Antisocial behaviour has been associated with exposures to both macro- and micro-
malnutrition in both the prenatal and postnatal periods (Liu & Raine 2006). This report aims
to summarize and evaluate empirical findings on malnutrition, especially deficiencies in iron
and omega-3 fatty acids (FAs), as a potential risk factor for the development of antisocial
behaviour. Iron deficiency has previously been identified as the most common single-nutrient
deficiency across the globe (Krecthmer, Beard & Carlson 1996). Although it is much more
prevalent in developing countries, it remains a problem in industrialized countries, especially
among young women of childbearing age (Murray-Kolb 2011). A standard Western pattern
diet, which is still rather popular in Great Britain, is characterized by a high consumption of
refined sugars, salt, saturated and trans fats and processed foods (Myles 2014). Such a diet
can lead to poor nutritional status, as it only provides a marginal supply of important
micronutrients (Benton 2007). Additionally, processed foods tend to contain a high
percentage of omega-6 FAs, which, although essential for human health in small amounts, if
consumed in excess, can interfere with the absorption of omega-3 FAs (Mesirow, Cecil,
Maughan & Barker 2017).
Over the years, iron deficiency has been repeatedly associated with a wide range of
conduct disturbances including problematic alcohol use, high-risk sexual behaviour, frequent
rule-breaking as well as delinquency (East et al., 2018; Liu & Raine, 2011; Robinson et al.,
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, 2018; Rosen et al., 1985). Webb and Oski (1974) reported that adolescent boys, aged 13-14,
suffering from iron-deficiency anaemia (IDA) tended to have more conduct problems than
non-anaemic controls. However, given that the study only involved male participants of a very
specific age, the obtained results cannot be generalized to a wider population. Additionally,
it is plausible that the increased number of conduct problems in the anaemic participants
were not exclusively caused by their IDA, rather, resulted from a more general nutritional
inadequacy, of which IDA was only an identified component. In support of this notion, Liu et
al. (2014) reported that while low iron and zinc status in combination were linked to increased
parent reports of externalizing behaviour problems in young Chinese children, IDA alone was
not.
On the other hand, Corapci, Calatrom, Kaciroti, Jimenez and Lozoff (2010) reported that
Costa Rican children, who had experienced chronic iron deficiency in infancy, had higher rates
of externalizing behaviour problems (aggression and defiance) from childhood to early
adolescence -as measured by mother ratings- compared to youngsters, whose iron status was
adequate in infancy. These effects remained significant, even after controlling for family
background and child variables. However, no such long-term, adverse effects of severe early
IDA were detected in young adulthood per youth self-reports. Nonetheless, the researchers
cautioned that this finding should be considered tentative, due to the lack of behavioural
ratings from other informants.
Deficiency in omega-3 FAs, namely, the parent short-chain fatty acid of a-linolenic acid
(ALA), and 2 long-chain fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid
(DHA), has also been linked to antisocial behaviour (Hibbeln, Ferguson & Blasbalg 2006).
Hibbeln (2001) analysed ecological data from 36 countries and found that there was an
inverse correlation between fish consumption and rates of death by homicide. Omega-3 FAs
cannot be synthetized by the human body and therefore must be obtained through diet. The
primary dietary source of EPA and DHA is seafood. Although humans have the ability to
convert ALA, which is found in many plant foods, into EPA and DHA, this process is often
rather inefficient (Chan, Ke & Chen 2015). Therefore, direct dietary intake of DHA and EPA
might be considered essential. Although the finding of Hibbeln’s ecological study falls short
of proving causality, it suggests that low omega-3 FAs intake may be linked to increased
aggression.
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