ADHD, Food Sensitivities and Elimination Diets: What the Research Says

ADHD Support & Awareness

Overwhelmed parents have long sought alternative explanations and remedies for their children with ADHD, including exercise for children with ADHD and dietary interventions.

We all know the unsettled feeling that comes from poor lifestyle habits. If we’re under-slept, overstimulated, poorly fed or dehydrated we suffer nervous system consequences, even as adults, which can make it more difficult to focus and get along with others. 

As nutrition science evolves, it’s unlikely we won’t find dietary strategies for most conditions. Research so far suggests nutrition and lifestyle factors may play a role in exacerbating behaviour among children with ADHD. 

Certainly the alternative health community has seized on preliminary research, and ADHD elimination diets are just a google away. But are they effective? And is the stress of a strictly controlled diet worth the effort for your child with ADHD?

Do Diet and Lifestyle Factors Affect ADHD Symptoms?

It seems so, but how is not yet understood. For children in general, research has suggested a link between sugar and food additives and behaviour, particularly hyperactivity.

Of course, lifestyle habits tend to exist in aggregate. Families which shun sugared beverages and red dye might also tend to be families with greater privilege and education who can also afford to purchase supplements, access psychological and medical care, make meals from scratch and spend time in nature as a family.

That said, some compelling evience suggests lifestyle can make an impact on ADHD symptoms. In 2020, a survey-based study of 286 children aged 7 -11 interviewed families about their water intake, sweetened beverage consumption, supplement use, reading, screen time, physical activity, and sleep. Children with ADHD were almost twice as likely to have fewer healthy behaviors, even after adjustment for age, sex, IQ, medication use, household income, and four comorbid psychiatric disorders. It’s worth noting that self-reporting in research often comes under fire for inaccuracy; however, the size of this study and controlling for other influencing factors such as income level and comorbidities makes the outcome worth investigating further.

Is ADHD Caused by a Poor Diet?

There isn’t yet a consensus on the exact causes of ADHD, but genetic factors seem to be the most agreed upon explanation. The U.S. National Institute of Health maintains: “Knowledge about the cause or causes of ADHD remains speculative. Consequently, there are no strategies for the prevention of ADHD.”

Perhaps lifestyle factors interact with the symptoms of ADHD, but they are not considered either a proven cause or treatment by the medical community.

Do Food Dyes and Additives Exacerbate ADHD Symptoms?

Of all the dietary interventions for the treatment of ADHD, none has been more regularly investigated than the elimination of food dyes and additives.

In children with and without ADHD, food dyes are often blamed for behaviour. A randomized trial of 267 U.K. children aged 3 and 8/9 administered beverages to two groups; one group received a beverage containing artificial food colouring and additives (AFCA) while the other received a placebo beverage.

The study found hyperactivity increased among the group receiving AFCAs. Following the study, in 2010, the European Union required that all foods containing artificial dye be labeled: “May have adverse effect on activity and attention in children.”

If you’re concerned that your child’s diet may be impacting their behaviour, replace foods and drinks which are artificially dyed or flavoured, or which contain sodium benzoate, for a week or two and observe any changes in their symptoms. There is no need for artificial dyes or flavours in the diet and you may safely exclude them or wean your child off of them and onto alternatives.

Omega-3 Supplementation for Children with ADHD

One of the most common dietary recommendations for children with ADHD is supplementation with Omega-3 fatty acids.  In a 2016 review of all evidence since 2000, study authors suggest the research “[shows] evidence for a successful treatment of ADHD symptoms.”

The authors were careful to state that treatment with polyunsatured fatty acids was more likely to be effective in patients with mild forms of ADHD. Given that Omega-3 supplementation is well tolerated and carries minimal risk, researchers suggest discussing its use with your family doctor or mental health professional. 

Elimination Diets for the Treatment of ADHD

Can eliminating certain foods from your child’s diet help to improve the symptoms of ADHD? That’s the question a team of researchers set out to answer in 2011. 100 children with ADHD aged 4–8 years were recruited for the 2011 study. Children were randomly assigned to either a controlled elimination diet, consisting of mostly rice, meat, vegetables, pears, and water, or sent home with merely the instructions to eat a “healthy diet.”

Of the 50 children on the controlled diet, 32 families reported improved ADHD symptoms according to a standard rating system. 18 of these 32 children experienced a relapse in behavioural symptoms when foods were reintroduced. The study also compiled earlier research and made a fair case for considering elimination diets in the treatment of young children, in families who are motivated to use dietary interventions in conjunction with prescribed medication. Some debate of the research methods used in the 2011 study ensued with critics pointing out the study included only 12 girls and only 6 children with Inattentive ADHD, one of three types of ADHD.

However, a 2014 review of the research to date concluded: “A consensus has emerged among most reviewers that an elimination diet produces a small aggregate effect but may have greater benefit among some children.” An uncontrolled 2020 study also suggested elimination diets improved ADHD symptoms in a majority of participants and recommended further controlled research. Larger scale, controlled research including both females and males as well as all 3 subtypes of ADHD are still needed.

If you’re considering dietary intervention to assist your child in managing ADHD symptoms, seek the help of a Registered Dietitian specializing in children and ADHD. The jury is still out on which dietary modifications, if any, will reliably produce a treatment outcome for children with ADHD.

Have you found success helping using dietary intervention to help your child with ADHD? Share below!