ADHD and Diet: Can What We Eat Impact Behaviour?

Attention Deficit Hyperactivity Disorder (ADHD) 

It is a common neurodevelopmental condition that affects both children and adults across the UK. It can influence concentration, impulse control, and activity levels, impacting everyday life at school, work, and home. But can diet play a role in managing ADHD symptoms? 

In this article, we explore the latest research on nutrition and ADHD, offering practical advice for families and carers.

Addressing ADHD Challenges in the UK: Diagnosis, Medication, and Access

Recent reports from the BBC highlight some of the critical pain points faced by individuals and families living with ADHD. Another BBC investigation revealed that NHS waiting times for ADHD diagnosis can stretch up to eight years in some areas, forcing many families to seek costly private assessments and medication. 

ADHD is characterised by a persistent pattern of inattention, hyperactivity, and impulsivity. Symptoms usually appear before the age of 12, although diagnosis can occur later, especially in adults. Common signs include:

• Difficulty concentrating or staying on task

• Restlessness or excessive fidgeting

• Impulsive actions, like interrupting or taking risks

• Disorganisation and forgetfulness

A review published in Nature pointed out features of the gut that might affect how ADHD shows up in children. ADHD affects around 5% of children worldwide and is more commonly diagnosed in boys than girls. While its exact cause is unknown, genetics, low birth weight, prematurity, epilepsy, and early brain injury may increase the risk.

Does Diet Influence ADHD Symptoms?

The link between diet and ADHD has been widely discussed, but scientific evidence remains limited. Nonetheless, some parents report improvements in behaviour after making dietary changes.

Food Additives and Hyperactivity

Certain artificial colours and preservatives may impact behaviour in some children. These include:

• E102 (tartrazine)

• E104 (quinoline yellow)

• E110 (sunset yellow)

• E122 (carmoisine)

• E124 (ponceau 4R)

• E129 (allura red)
  
  

These are commonly found in sweets, fizzy drinks, and processed snacks, which also tend to be high in sugar and low in nutrients. Keeping a food and behaviour diary can help identify if these additives affect your child. If so, consulting a registered dietitian to trial an elimination diet may be beneficial.

Sugar, Gluten, and Food Sensitivities

Sugar

• Despite popular belief, research does not support a direct link between sugar intake and hyperactivity. Excitable behaviours are more likely at parties or celebrations where sugar is consumed in high amounts.

Gluten

• There is no clear evidence that gluten affects ADHD symptoms. However, children with coexisting conditions like autism spectrum disorder (ASD) may already follow restricted diets, so any changes should be made carefully.

Food Sensitivities: 

• Some children may react behaviourally to specific foods, but this varies widely. Professional guidance is recommended before making significant dietary changes.

“Few Foods” Diet

• This highly restrictive diet allows only a handful of foods and is not recommended without medical supervision. Nutritional deficiencies are likely, and strong evidence of effectiveness is lacking.

Important Nutrients for ADHD

Some children with ADHD may have low levels of iron, zinc, or magnesium. Testing levels and supplementing where necessary, under a GP or consultant’s guidance, can support overall health.

• Iron-rich foods: red meat, eggs, tofu, fortified cereals, pulses

• Zinc sources: meat, dairy, seeds, fortified bread

• Magnesium-rich foods: fish, nuts, seeds, green vegetables

A general multivitamin may also be considered for those with restrictive eating habits.

Omega-3 Fatty Acids

Omega-3s are essential for brain function and may improve some ADHD symptoms. Studies suggest benefits from supplements containing EPA, DHA, and GLA. Natural sources include:

• Oily fish (sardines, salmon, mackerel)

• Walnuts

• Chia seeds

• Flaxseed

• Omega-3 enriched eggs and dairy

How Medication Impacts Appetite

Common ADHD medications like methylphenidate and dexamphetamine can reduce appetite or cause stomach discomfort. Regular growth monitoring and food planning are key. 

Tips to support appetite:

• Offer a larger breakfast before medication

• Provide a calorie-dense dinner

• Use energy-rich snacks

• Discuss weekend medication breaks with the care team

• Fortify foods or consider nutritional supplements if needed

While diet cannot cure ADHD, it may help manage symptoms alongside medication and behavioural support. Removing certain additives and increasing omega-3 intake show promise, but restrictive diets should be approached with caution due to nutritional risks. Always seek advice from a registered dietitian or healthcare professional before making changes.

Learn more on how Back to Balance Test could helps identify food triggers that may exacerbate symptoms. Even a 10-20% improvement in dietary management can have a noticeable positive impact on focus and overall health.

FAQs

Q: Can a change in diet replace ADHD medication?
A: No. Dietary changes should never replace prescribed medication. While certain nutritional strategies may support overall health and possibly ease some symptoms, medication remains the most evidence-based treatment for managing ADHD symptoms. Always consult a healthcare provider before making any changes.

Q: Is there a specific “ADHD diet” that works for everyone?
A: There is no one-size-fits-all ADHD diet. While some children may benefit from avoiding specific additives or increasing omega-3 intake, others may not see any change. It’s best to monitor food and behaviour using a diary and work alongside a dietitian to tailor a suitable approach.

Q: Can food allergies or intolerances cause ADHD?
A: There is no evidence that food allergies or intolerances cause ADHD. However, certain foods might affect behaviour or concentration in some individuals. Identifying and managing these reactions should be done under the guidance of a qualified nutrition professional.

Q:  How can I encourage my child with ADHD to eat a varied diet, especially if they are a fussy eater?
A: Start with small changes offer familiar foods alongside new ones, make meals visually appealing, and involve your child in shopping or cooking. Avoid pressure and try to maintain a calm mealtime environment. If appetite is affected by medication, focus on high-calorie snacks and nutrient-dense meals at times when they are more likely to eat.

References 

Food Standards Agency (2019). Food Additives.
https://www.food.gov.uk/safety-hygiene/food-additives#food-colours-and-hyperactivity

NICE (2018). Attention Deficit Hyperactivity Disorder: Diagnosis and Management. Clinical Guidance. https://www.nice.org.uk/guidance/ng87

Wolraich, M. L. et al. (1995). The effect of sugar on behaviour or cognition in children: A meta-analysis. https://pubmed.ncbi.nlm.nih.gov/7474248/

D. Gkougka et al., “Gut microbiome and attention deficit/hyperactivity disorder: a systematic review,” Pediatr. Res., vol. 92, no. 6, pp. 1507–1519, Dec. 2022, doi: 10.1038/s41390-022-02027-6. https://rdcu.be/ejaMT

Author: Gyanisha Gothi, ANutr AfN Registered Associate Nutritionist Gyanisha Gothi is a Registered Associate Nutritionist (ANutr) with a strong scientific background and a passion for turning complex nutrition research into practical, personalised guidance. With an MSc in Clinical and Public Health Nutrition from UCL (Merit), a BSc in Biochemistry, and additional certifications in Food Allergy & Intolerance Training and Good Clinical Practice (NIHR), she brings a well-rounded blend of academic and clinical expertise. Dedicated to evidence-based practice, Gyanisha supports individuals in improving gut health, strengthening metabolic wellbeing, and making sustainable lifestyle changes, delivering a warm, client centred approach at Back to Balance.