Artificial food coloring has long been suspected of contributing to diagnoses of ADHD, but a new study from Perth’s Telethon Institute for Child Health Research shows an association between ADHD and the broader diet patterns of a ‘Western-style’ diet in adolescents. The research has just been published online in the international Journal of Attention Disorders.
Leader of Nutrition studies at the Institute, Associate Professor Wendy Oddy, explained that the researchers looked at the dietary patterns of 1800 adolescents from the Raine Study and classified diets into ‘Healthy’ or ‘Western’ patterns. The Raine Study is an ongoing health research project which has followed a large group of mothers and their offspring over the past 18 years.
What researchers found is that a diet high in foods typical of the standard Western diet was associated with more than double the risk of having an ADHD diagnosis, compared with a diet low in the Western pattern–even after adjusting for other social and family influences.
“We looked at the dietary patterns amongst the adolescents and compared the diet information against whether or not the adolescent had received a diagnosis of ADHD by the age of 14 years. In our study, 115 adolescents had been diagnosed with ADHD, 91 boys and 24 girls.”
A ‘healthy pattern’ is a diet high in fresh fruit and vegetables, whole grains and fish–it is generally higher in omega-3 fatty acids, folate and fibre. A ‘Western pattern’ is a diet generally higher in total fat, saturated fat, refined sugar and sodium.
When they looked at specific foods, having an ADHD diagnosis was associated with a diet high in these five food categories:
1. Fast foods
2. Processed meats
3. Red meat
4. High fat dairy products
Oddy says that, “a Western dietary pattern may indicate the adolescent has a less optimal fatty acid profile, whereas a diet higher in omega-3 fatty acids is thought to hold benefits for mental health and optimal brain function. It also may be that the Western dietary pattern doesn’t provide enough essential micronutrients that are needed for brain function, particularly attention and concentration, or that a Western diet might contain more colours, flavours and additives that have been linked to an increase in ADHD symptoms. It may also be that impulsivity, which is a characteristic of ADHD, leads to poor dietary choices such as quick snacks when hungry.”
Dr Oddy said that although this study suggests that diet may be implicated in ADHD, more research is needed to determine the nature of the relationship.