Attention-deficit/hyperactivity disorder (ADHD) is the most common neurodevelopmental condition in children affecting around 5% of the population. It is caused by a combination of genetic and environmental factors and varies in symptoms and severity. Some children benefit from medication but may experience negative side effects, therefore dietary interventions have been the subject of much research over the years.

Dietary interventions are divided into 2 categories, either removal or supplementation of certain elements:

  1. Removal of artificial food colours, food additives, sugar, dairy or gluten-free diets, and “few foods” or “elimination” diets,
  2. Increasing certain nutrients such as fish oils, vitamins and minerals (B & C vitamins, iron, magnesium, and zinc)

Two review articles (referenced below) that analysed 52 research studies found that there was no strong evidence to support any of the above dietary interventions apart from some possible mixed findings to support the “Few Foods” diet and supplementation with fish oils which is explained further below.

Few Foods Diet or Elimination Diet

The “Few Foods Diet” is the elimination of potential allergens as well, such as wheat, dairy, certain meats, carbohydrates, fruits, and vegetables. It must be followed with the guidance of a qualified health professional, such as Accredited Practising Dietitian, and with approval of your child’s GP and/or paediatrician. The Few Foods Diet is designed to be followed short term (2-5 weeks) in which the child is only allowed to eat a few different hypo-allergenic foods (eg, rice, lamb, lettuce, pears, water), then a broader range of foods are gradually reintroduced to identify the potential trigger of ADHD symptoms. This can take up to a year while foods are slowly reintroduced. However, most parents find it a difficult diet to do, therefore adherence is poor, it’s disruptive to social life and can result in nutritional deficiencies if followed long term. As mentioned previously, while there is some evidence to support this diet, it’s not convincing.

Fish oils supplementation

Studies conducted to date show some possibly promising signs that fish oil supplementation can be beneficial to alleviate the symptoms of ADHD. Furthermore, fish oils are a convenient and relatively easy supplement to give with minimal side effects. Therefore, this is a reasonable to option to consider in conjunction with other therapies and/or medication, but not as a sole source of treatment.

Conclusion

There is a small amount of evidence to support elimination diets (for the short term only) and fish oil supplementation but the effects shown are small and individual. These dietary interventions can be considered in conjunction with other therapies and/or medication but not as a sole source of treatment. It is advisable to seek guidance from an Accredited Practising Dietitian (APD) such as Dietitian For Kids (www.dietitianforkids.com.au) with experience in this area if considering dietary treatments and to also discuss it with your child’s GP or paediatrician.

References:

  • Rytter MJH, Anderson LBB, Houmann T, et al. Diet in the treatment of ADHD in children – a systematic review of the literature. Nord J Psychiatry 2014; 64:1-18.
  • Rucklidge JJ, Taylor MR, Johnstone JM. Do Diet and Nutrition Affect ADHD? Facts and Clinical Considerations. 2018. Psychiatric Times, Vol 35, Issue 9, Volume 35.