The effect of dietary education on ADHD, a randomized controlled clinical trial
Ghanizadeh and Haddad Annals of General Psychiatry
The effect of dietary education on ADHD, a randomized controlled clinical trial
Ahmad Ghanizadeh 0 1 2
Behzad Haddad 1
0 Department of Psychiatry, School of Medicine, Shiraz University of Medical Sciences , Shiraz , Iran
1 Research Center for Psychiatry and Behavioral Sciences, Department of Psychiatry, School of Medicine, Shiraz University of Medical Sciences , Shiraz , Iran
2 Department of Neuroscience, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences , Shiraz , Iran
Background: The purpose of this research was to study the effectiveness of the overall dietary intervention rather than a single nutrient on children with attention deficit hyperactivity disorder (ADHD). Methods: This is a randomized controlled trial conducted at a child psychiatry clinic in Iran. Participants were 106 children and adolescents with ADHD. One group received methylphenidate plus dietary recommendations, while the other group only received methylphenidate. ADHD DSM-IV checklist was used to assess inattentiveness and hyperactivity/impulsivity scores at baseline and at the end of the trial. Results: The results revealed no significant difference between the two groups regarding mean age, gender ratio, body mass index, baseline inattentiveness score, and baseline hyperactivity score. Linear regression analysis considering the covariant variables showed that the inattentive score at the end of the trial was significantly associated with the mean change of favorite diet scores. Conclusion: This is the first clinical trial examining the effect of overall dietary characteristics rather than a single nutrient on the children formally diagnosed with ADHD. According to the results, un-favorite diet had no effects on inattentive or hyperactivity/impulsivity score. Encouraging the children with ADHD to increase their intake of recommended diet markedly improves their attention. Trial registration: The trial was registered at the Iranian Clinical Trials Registry (Irct ID: IRCT201311303930N29).
ADHD; Attention; Diet; Clinical trial; Sugar; Cacao; Artificial food color
-
Introduction
Attention deficit hyperactivity disorder (ADHD) is a
common psychiatric disorder in children and
adolescents. The neurobiology of ADHD is not clearly known.
However, claims have been made that diet is associated
with ADHD and infantile malnutrition causes
longlasting attention problems [1]. However, there is no
scientific evidence showing that diet causes ADHD.
There are also some reports about the association of
junk food [2], Western dietary pattern [3], and fast
food [4] with ADHD symptoms.
Sweets and sugar are also believed to be associated
with ADHD symptoms [4,5]. However, this assumption
needs to be examined since some studies have not
shown any association between sugar and behavioral
problems [6,7]. On the contrary, another study reported
that less consumption of sugar from fruit snacks
increased the risk of ADHD [8]. Moreover, none of the
studies has examined the effect of sugar on ADHD, but
they have assessed its association with behavioral
problems and cognition [6,7].
A 21-day, double-blind, placebo-controlled,
repeatedmeasure study showed that ingestion of a synthetic food
coloring was associated with irritability, restlessness, and
sleep disturbance [9]. Toxicological, anti-nutritional,
and hypersensitivity are the three supposed possible
mechanisms for the effect of artificial food colors on the
childrens behaviors [10]. However, evidence-based
information is needed to support the potential efficacy of
restricted diet on ADHD symptoms [11,12]. In a
randomized controlled clinical trial, artificial food colorings
and a preservative did not show any effects on the
childrens behavior [13]. On the other hand, a systematic
review showed that free fatty acid supplementation slightly
reduced the ADHD symptoms and that exclusion of
artificial food colors might reduce the symptoms in those
with food sensitivities [14].
One other study reported that food supplements might
be as effective as methylphenidate in improvement of
some ADHD symptoms [15]. Nonetheless, more
evidence regarding the efficacy of restricted diets is
needed [14]. Although omitting some items is
supposed to be helpful, their efficacy has not been
assessed in controlled clinical trials [16]. In fact, it is
a neglected research area [17]. Moreover, current
literature suffers from publication bias and small
nongeneralizable samples [18]. Thus, further investigations
are recommended to be conducted on the effect of diet
on ADHD [18].
One study showed that intake of sweetened desserts,
fried food, and salt are associated with more attention
and behavioral problems while a balanced diet, regular
meals, and a high intake of dairy products and
vegetables are associated with less attention and behavioral
problems [19]. However, the cross-sectional design of
that study did not allow the authors t (...truncated)