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Written by Written by Ailisha-L. N | Accredited Exercise Physiologist, PsychPhys™, ESSAM, AES, AEP

What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder involving inattention, hyperactivity and impulsiveness. It is one of the most common disorders among kids but also affects many adults.

The exact cause of ADHD is unclear, however research shows that genetics do play a major role. Other factors such as environmental toxicity and poor nutrition during infancy have also been implicated.

ADHD is believed to originate from low levels of dopamine and noradrenaline in the region of the brain responsible for self-regulation.

Nutrition and Symptoms

The science behind the effects of food on behaviour is still quite new and controversial. However, certain foods do affect behaviour. For example, caffeine can increase alertness, chocolate can affect mood and alcohol can change behaviour.

Studies have found that vitamin and mineral supplements can reduce antisocial behaviour in children and polyunsaturated fatty acids have been shown to decrease violent behaviour.

One study followed 800 children suspected of hyperactivity, 75% of them improved while on an AFC-free (Artificial colourants) diet but relapsed once given AFC’s again.

Another study found that hyperactivity was increased in 1873 kids consumed AFC’s and benzoate which is also a preservative.

There were 12 studies done on the ‘few foods elimination diet’, each study lasted between 1-5 weeks and included a total of 21-50 children. Out of the 12 studies done, 11 found a statistically significant decrease in ADHD symptoms in 50-805 of the participants while the other study only found an improvement in 24% of the children. From all the food eliminated cows milk and wheat were the two most common offenders.

Exercise and Symptoms

Almost all studies done have found exercise-related improvements with small to large effects on ADHD symptoms, executive functions, academic performance or motor skills.

One study done in 2016 found that exercise had a significant effect on ADHD functional outcomes. Longer exercise intervention duration was associated with larger consisted positive effects.

A separate study done in 2021 found that physical activity could improve ADHD-related symptoms, in particular inattention symptoms. They also found that Closed-skill (eg. trampolining, golf swing, diving from a platform) and open skill activities (e.g. netball, football, hockey) could also benefit hyperactivity/impulsivity and inattention symptoms respectively.

A systematic review and a meta-analysis were done in early 2021 to assess the impact of exercise interventions in children and adolescents with ADHD and again found that exercise intervention improved the overall executive functions of children and adolescents with ADHD. Exercise interventions also had a moderate-to-large positive effect on inhibitory control and cognitive flexibility. They concluded the study by stating that: Chronic sessions of exercise interventions with moderate intensity should be incorporated as treatment for children with ADHD to promote executive functions.


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