Sugar & children's behaviour

facT sheeT
Sugar & children’s behaviour
Sugar can be used in moderation in children’s diets, but is there reason to exclude it
altogether? Numerous myths persist about the effects of sugar on children, particularly
related to behaviour. However, research into sugar and behaviour shows that sugar
is not the villain it was once considered to be.
Despite the results of carefully controlled
additions and avoidances, clearly illustrated
illustrate the varied beliefs and sources of
studies there is still a strong belief among
the level of concern some people had about
information caregivers rely on.1
some health professionals and caregivers
sugar consumption – even at that time.1
In the last 20 years, while much scientific
that sugar, particularly refined sugar or
Among 103 children a specific alteration
study has been completed on possible
sucrose, does affect children’s behaviours.
to the diet was seen in 48 cases. There
dietary causes of hyperactivity (showing
were 38 avoidances, 20 additions and in
While information on this subject is
no association with sugar intake), parents
10 children there were both. In five cases
dated, research largely conducted since
continue to receive misinformation about
sucrose was avoided due to health beliefs,
the mid 90s illustrates that there is no
the role of sugar on childhood behaviour
perceived hyperactivity, overweight and
clear association between sugar intake
from the same sources.
constipation. Interestingly, the source of
and inappropriate behaviour patterns in
advice directing these sucrose avoidances
The following information presents the
childhood.
were media, family and in one instance,
most up-to-date information on the subject
A New Zealand-based study undertaken in
a physiotherapist. While the researchers
of sugar and behaviour.
1989 looking at the changes parents made
acknowledge these dietary adjustments
to their child’s diet, particularly deliberate
were not harmful to the children, they do
Hyperactivity
Hyperactivity and
A review of research explores the possible link between
sugar intake
sugar intake and excessive activity in children. Hyperactivity
or ADHD (Attention Deficit Hyperactivity Disorder) are often
The interest in sugar and hyperactivity peaked in the mid 1970s when several
used synonymously. However, there are subtle differences.
cross sectional studies suggested an association between sugar intake and
ADHD can be considered ‘true hyperactivity’.
hyperactivity.
ADHD is characterised by difficulty in delaying gratification,
However, a major limitation of cross sectional studies is that it is impossible to
inattentiveness, distractibility, impulsive behaviour, anxiety
determine a cause and effect relationship i.e. it was equally possible that the
and excessive motor activity. It is often accompanied by
behaviour caused the increased sugar intake, rather than the increased sugar
emotional immaturity, aggressiveness and poor academic
intake causing the behaviour.3 It was also likely that a third variable such as
performance.2
different parental discipline style may have been a causal factor. Another problem
The prevalence of ADHD, as opposed to the child simply
was that these studies were based on retrospective meal intakes providing
being overactive at times, is very low. It has been estimated
data on what children had been eating a week or so before the assessment
that approximately 3% of children may suffer from ADHD
of behaviour, whereas sugar’s effect on behaviour could be more immediate
with the disorder six to nine times more common in boys
e.g. within 30 to 60 minutes from sugar consumption.2
than girls.2 Clearly the perceived frequency is far higher.
A more detailed assessment of this issue has required intervention studies. This
There has been much speculation about the causes of
is where a dietary challenge method is used, along with attempts to replicate real
ADHD and both genetic and environmental factors have
life situations reported by parents, to demonstrate adverse effects of refined sugar
been associated with it.2
(sucrose) on children’s behaviour. In one study, children’s behaviour was rated for
Nutritional factors such as food additives, food sensitivities/
several hours after consuming either a sugar-containing food or beverage or a
allergies, fatty acid deficiencies and refined sugar have all
placebo containing an artificial sweetener (aspartame or saccharine).3
been linked to ADHD at times. While there is some evidence
The study was double blind. The children, their parents and researchers were
that children with behavioural problems are sensitive to one
unaware of the composition of foods or drinks consumed.
or more food components, researchers agree that ADHD is
a problem of complex etiology.
continued over
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facT sheeT
continued
Hyperactivity and sugar intake
Crossover procedures were also employed whereby children were given the sugar-containing
Limitations
item on one day and a placebo on another, with the order of presentation varying among the
children. Results showed that even when sucrose or aspartame intakes exceeded typical dietary
of the
levels that there were no affects on the children’s behaviour or cognitive function.3
Behaviour and cognition
research
Other than research investigating a
Behaviour and cognition are complex issues that can be influenced by a magnitude of factors
positive role for sugar and cognition,
including social, familial or psychological. Nutrition is only one aspect involved in performance. It
there has been little research since
is now generally accepted that sugar consumption is not linked to adversely affecting children’s
the mid 90s. Many studies included
behaviour.4
in the meta-analysis had a small
Following the research of the mid 90s, researchers conducted a meta-analysis of results. They
sample size, so there is limited
examined intervention studies looking at the effects of sugar intake on the behaviour or cognition
power to detect significant effects.
of children, and reviewed 23 studies conducted between 1982 and 1994.5 The researchers
Furthermore, dosages used in the
examined the cumulative results of studies which identified any effects of sugar on the behaviour
challenge studies may have been
or cognitive performance of children. Subjects included both normal and reportedly hyperactive
too small to have significant effect
children. The studies reviewed included a combination of academic tests, motor skills tests and
when compared to children’s normal
direct observation. Results of this meta- analysis found that sugars (mainly sucrose) do not affect
daily intakes.2
the behaviour or cognitive performance of children.5 These findings were further supported in
Participant selection is another
another recent review. It was also highlighted that the best way to ensure optimal cognition and
issue. What are the criteria for sugar
behaviour was to have good dietary habits.6 However, it is possible that there may be a small
sensitivity? Studying the reaction of
effect of sugar or effects on subsets of children.5
so-called ‘sugar sensitive’ children
More recently a further review concluded there is little empirical evidence to support the
to sugar ingestion cannot be
effectiveness of dietary restrictions in treating child psychiatric disorders, in particular, autism
generalised to the normal population
and ADHD.7
of children and vice versa.
In some instances, research indicates that intakes of sugars can in fact improve performance on
Hyperactive children may have
cognitive tasks from infants to the elderly.6,8 It appears that the brain is sensitive to short-term
multiple sensitivities, so eliminating
fluctuations in glucose supply and therefore it might be important to maintain even levels during
only one of the substances e.g. sugar
the day to optimise cognition. The mechanism by which glucose enhances memory is poorly
or a food additive may not make a
understood.9 However one area which future research should focus on is to investigate the
significant difference in behaviour.2
effect of ingestion of foods with a low Glycaemic Index (GI).9
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facT sheeT
Why results of research differ
from expectations
Parents’ beliefs and expectations can have a major effect on how they perceive behaviour
and how they interact with children.10 The most common explanation as to why there is a
so-called “sugar high” is that foods high in sugar are often given to children in contexts which
are celebratory, rewarding and exciting.
For instance, children become excitable at birthday parties and holidays, which generally coincide
with high sugar intakes from foods like fizzy drinks, lollies or cakes. Variation in their behaviour
may be mistakenly correlated with sugar consumption. This, along with negative media publicity
on sugar, may encourage current misunderstandings.5
Further research needed
Additional studies are needed to test for differential effects of sugar on restricted subsets of
children i.e. there may be a subset of children with behavioural problems who are sensitive to
one or more food com ponents. The studies discussed in this paper show that not all hyperactive
children respond to the same offending substance.
Summary
Current research provides little support for the effect of sugar on behaviour of most children. Consumed in moderation as part of
a healthy, balanced diet, sugar poses negligible risks to most children and its addition can assist with consumption of nutritious
foods that may otherwise be unacceptable.
It is strongly recommended that removal of any food, component or ingredient from the diet of a child should only be done under
the advice and supervision of an appropriate health professional, such as an allergy specialist or dietitian.
Last updated November 2008
RefeRences
i. Ford rPK, dawson KP, Mogridge n. children’s diets; what do parents
The Sugar Research Advisory
add and avoid? nZ Med J 1989; 102:443-445
Service (SRAS) is a public
2. Schnoll r, Burshteyn d, cea-Aravena J. Applied Psychophysiology and
Biofeedback; 2003; 28;1;63-75
information service funded by
3. Wolraich ML, Lindgren S, Stumbo Petal. effects of diets high in sucrose
the New Zealand Sugar Company
or aspartame on the behaviour and cognitive performance of children.
Limited. The SRAS is advised by
n engi J Med 1994; 330:301-307
a panel of independent health
4. institute of Medicine (ioM), 2002. dietary carbohydrates: sugars and
and nutrition experts whose role
starches. dietary reference intakes for energy, carbohydrate, Fiber, Fat,
Fatty Acids, cholesterol, Protein, and Amino Acids. national Academies
is to review all SRAS-produced
Press, Washington.
information and guide the SRAS
5. Wolraich ML, Wilson oB, White JW. the effect of sugar on behaviour
on issues of health and nutrition.
or cognition in children. JAMA 1995; 274; 20:1 617-1 621
6. Bellisle F. effects of diet on the behaviour and cognition of children.
British Journal of nutrition. 2004;92(2):S227-S232
Contact details are:
7. cormier e, elder JH. diet and child behavior problems: fact or fiction?
The Secretariat
Pediatr nurs. 2007;33(2):138-43
SRAS
8. Busch cr et al. the effects of a confectionary snack on attention in
PO Box 5224
young boys. Physiol Behav. 2002;77:333-340
Wellesley Street
9. Benton d and nabb S. carbohydrate, memory and mood.
Auckland
nutr rev. 2003;61:S61-S67
Fax 09 308 9456
10. Hoover oW, Milich r. effects of sugar ingestion expectancies on
mother-child interactions. J Abnorm child Psychol 1994; 22:501-515
Email info@sras.org.nz
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