Overview
A new 2026 study found that children with ADHD who consumed less vitamin A, vitamin C, and selenium had significantly worse symptoms across the board: more inattention, more hyperactivity, more behavioural and social problems. All three are antioxidants, which lines up with existing research showing that ADHD bodies tend to have weaker antioxidant defenses to begin with. Since lower antioxidant intake was associated with worse ADHD symptoms, it might be worthwhile to increase your total antioxidant intake.
What they researched
Pinto, Correia-de-Sá, Gonçalves et al. (2026) recruited 76 children aged 6 to 10 years from public hospitals, private clinics, and the community in Portugal. There were 43 with a clinical ADHD diagnosis and 33 neurotypical controls.
To assess what children were actually eating, parents completed 3-day consecutive food diaries accompanied by photographs of meals.
Differences in nutrient intake
While there were no overall food pattern differences between the groups, when the researchers looked at individual nutrients, there were three major differences:
- Monounsaturated fats (MUFAs): children with ADHD consumed significantly less (p = 0.003). MUFAs are found in olive oil, avocados, nuts, and many animal fats.
- Polyunsaturated fats (PUFAs): also significantly lower in the ADHD group (p = 0.010). PUFAs include omega-3 and omega-6 fatty acids.
- Vitamin C: significantly lower in the ADHD group (p = 0.014).
Continued below…
Nutrient intake and ADHD severity
The researchers also connected nutrient intake with ADHD symptom severity. They found that:
Lower vitamin A intake correlated with:
- Higher inattention (CPRS-R:S)
- Higher hyperactivity/impulsivity
- Higher overall ADHD severity index
- More social problems (CBCL)
- More externalising problems
Vitamin C was associated with higher hyperactivity/impulsivity and a higher ADHD index score.
Lower selenium was associated with greater somatic complaints, social problems, thought problems, rule-breaking behaviour, aggressive behaviour, and externalising problems.
Interestingly, MUFAs and PUFAs — despite being significantly lower in the ADHD group — did not show significant correlations with specific symptom domains. Lower intake was associated with diagnosis, but not with symptom severity in the way vitamins A and C and selenium were. This may be connected to how recent research finds that omega-3 supplementation has no effect on ADHD symptoms, despite how important it is to brain health.
Limitations
This is an observational, cross-sectional study — meaning it captured one snapshot in time. We cannot conclude from this research that low vitamin A, C, or selenium intake causes ADHD symptoms, or that increasing these nutrients would reduce them. The relationship could run in both directions: ADHD-related behavioural patterns (food selectivity, difficulty sitting through meals, attentional demands at mealtimes) may contribute to lower nutrient intake, rather than the other way around. The sample was also small, and we need more research to make any conclusive statements.
What to Take Away
Since lower antioxidant intake was associated with worse ADHD symptoms, it might be worthwhile to increase your total antioxidant intake. After all, we even have genetic research showing that people with ADHD have slightly worse antioxidant systems.
Here is where you can find the three specific antioxidants in this study:
Vitamin A: liver, eggs, dairy, and orange/yellow vegetables
Vitamin C: kiwi, citrus, and strawberries
Selenium: Brazil nuts, seafood, and eggs
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As always, remember: none of this really matters if it’s stressing you out. Something is always better than nothing! If you can give yourself or your kid some orange juice or milk with breakfast, you’re doing great.
This article summarizes the research from the aforementioned studies and the author’s knowledge. It is for educational purposes only. Nothing in this article constitutes medical advice.
