ADHD is defined by the Diagnostic and Statistical Manual of Mental Disorders (V) as a complex, multi-faceted, neurodevelopmental disorder often co-occurring with externalizing symptoms including oppositional and conduct disorder-related behaviours. There are two recognized, diagnostic sub-types:
- Predominantly inattentive (ADD)
- Combined hyperactive-impulsive (ADHD)
Typical behaviours of inattention (e.g., as witnessed in Attention Deficit Disorder / ADD) and/or the combined hyperactive-impulsive (ADHD sub-type) are present before the age of 12 but often observable in children as young as 2 years of age.
The Hyperactive-Impulsive subtype
In regards to the hyperactive-impulsive nature of ADHD, characteristic behaviors include an inability to sit still for any period of time; fidgeting, tapping, squirming and general restless behavior. Children with this sub-type will lose interest in assigned tasks quickly and have difficulty following instructions. They are prone to talking excessively, and making frequent and repetitive interruptions during the conversations of others. Often children with ADHD are unable to play quietly, and are constantly on the go, as if driven by a motor .
The Inattentive subtype
The inattentive subtype (ADD) is characterized by an inability to pay close attention to detail. Children will often make careless mistakes in school and homework. They have difficulty paying attention and appear not to be listening even when spoken to directly. Consequently, they fail to complete school and homework and/or chores around the home and are instead prone to wondering off, easily distracted. Children and adults with ADD persistently lose items necessary for everyday functioning, are often messy and disorganized with little or no concept of time. This inattentiveness and general absent-minded behavior can lead to crucial appointments being missed which then create further complication and chaos in the young person’s life. The disorder, although typically diagnosed in childhood, frequently persists into adulthood and places those affected at risk for a variety of irregularities in personality development. Clinicians generally agree that symptoms of hyperactivity diminish with age but inattentiveness persists into adulthood.
Although the main line of treatment for children with ADHD is behavioural therapy and/or stimulant medication, a growing body of evidence has suggested a potential role for omega-3 highly unsaturated fatty acids (HUFAs) as an adjunct therapy or alternative consideration for those children who are either treatment resistant or non-responders. A recent meta-analysis by Bloch and Qawasmi (2012) evaluated the outcomes of 10 randomised, placebo-controlled, omega-3/6 dietary intervention trials in 699 children with symptoms of ADHD. The results showed a small to moderate effect size for efficacy of omega-3 fatty, with EPA being particularly effective in reducing clinical symptoms of ADHD . However, much research is needed in this area, in order to better extrapolate the role of nutrition in ADHD, This will be discussed in more detail in the Dietary Changes section of the website.