Supplements for ADHD: What Trials Found and Where Evidence Is Weak
What reviews and guidelines say about omega-3, zinc, iron and other supplements for ADHD, where the evidence is weak, and why supplements do not replace assessment or treatment.
Content last updated . This page has not been medically reviewed.
Start here: ADHD needs assessment, and supplements are not treatment
ADHD (attention-deficit/hyperactivity disorder) is a neurodevelopmental disorder, with symptoms that usually begin in childhood and often continue into adulthood. [1] NCCIH states that conventional treatment is proven to reduce ADHD symptoms in most children and adults. [2] This page is information only. Do not stop, replace or change a prescribed medicine because of a supplement; talk to the prescriber. For adults, see ADHD in adults, and for why prescription stimulants are a different category from supplements, see why they are not interchangeable.Children and iron: iron supplements carry risks, including death in the case of overdose. [3] If a child has swallowed supplements, call 911 or Poison Help at 1-800-222-1222 (US); see iron overdose and child safety.
What official sources say
NCCIH reports that the results of many studies of complementary approaches for ADHD are mixed or have not shown improved symptoms (page last updated May 2019). [2] In England, the NICE guideline NG87 (published 2018, updated 2019) says healthcare professionals should stress a balanced diet, good nutrition and regular exercise, and not advise or offer dietary fatty acid supplementation for treating ADHD in children and young people. [4] This is a UK recommendation and other countries' guidance may differ.What reviews and trials found
Labels: established nutritional role / deficiency treatment, promising but limited, mixed, insufficient evidence, no good evidence of benefit. Most trials below are in children and teens; Proper evidence not found for adult-specific supplement reviews we could read (PubMed searches for adults, ADHD, dietary supplements, and omega-3).| Ingredient | What the source found (population, comparator) | Label |
|---|---|---|
| Omega-3 / PUFA | Cochrane 2023: 37 trials in children and teens; high-certainty evidence of no effect on parent-rated total ADHD symptoms, and low-certainty evidence of improvement on one other measure. [5] | No good evidence of benefit |
| Omega-3 and cognition | 24 trials in healthy and ADHD groups: no improvement in cognitive measures in the ADHD subgroup. [6] | No good evidence of benefit |
| Omega-3 and vitamin D (adjunct) | An umbrella review reported emerging evidence of adjunctive benefit, and said larger trials were needed; results for dietary interventions were nonsignificant or contradictory. [7] | Mixed |
| Zinc | 6 trials, 489 school-aged children: improvement in total ADHD scores but not in hyperactivity or inattention; certainty moderate to very low. [8] | Mixed |
| Iron | Three RCTs (124 participants) of iron for ADHD hyperactivity: no significant difference from placebo; quality of evidence very low. [3] A broader meta-analysis in non-anemic children and menstruating adults (not an ADHD-only group) found no improvement in attention. [9] | Insufficient evidence |
| Magnesium, vitamin D | A review of 14 RCTs reported varying degrees of effectiveness, with study diversity and short-term outcomes as limitations. [10] | Insufficient evidence |
| Citicoline, phosphatidylserine | 11 studies, five in children with ADHD: improved attention in three, no difference in two; authors concluded the evidence does not support them as cognitive enhancers in mental disorders. [11] | Insufficient evidence |
| Ginkgo, carnitine, St. John's wort, pine bark extract | NCCIH: research is limited and has not shown these improve ADHD symptoms. [2] | Insufficient evidence |
Zinc and iron deficiency are different from ADHD: a clinician tests and treats a real deficiency. See zinc and iron. Omega-3 is covered in omega-3 evidence by use, and L-theanine in L-theanine for attention and ADHD.
Frequently asked questions
Do supplements treat ADHD?
No supplement has been shown to treat ADHD. NCCIH says results are mixed or unproven, and conventional treatment is proven to reduce symptoms in most people. [2]
Does omega-3 help ADHD?
A Cochrane review found high-certainty evidence that omega-3 and other fatty acids had no effect on parent-rated total ADHD symptoms in children and adolescents. [5] NICE advises against offering fatty acid supplements for ADHD in children and young people. [4]
Does zinc help ADHD?
A meta-analysis of six trials found improvement in total scores but not in inattention or hyperactivity, with moderate to very low certainty. [8]
Can I use a supplement instead of ADHD medicine?
Supplements are not shown to replace treatment. Do not change a prescribed medicine without the prescriber. [2]
Are nootropics safe for children with ADHD?
Proper evidence not found for safety and benefit of nootropic supplements in children with ADHD in the sources we read. Ask a clinician or pharmacist before giving any supplement.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Limits and uncertainty
- Small trials, short follow-up and different products and populations limit every conclusion above. [5][10]
- Parent ratings, test scores and clinician ratings can differ; a change in one is not a change in daily functioning.
- Findings in children do not transfer to adults, and the reverse.
- Reviews can reach different conclusions on the same ingredient (for example omega-3), depending on which trials and outcomes are counted. [5][7]
Safety and who should ask first
NCCIH notes dietary supplements may have side effects and interact with some medicines, and that St. John's wort can weaken the effects of many medicines, including crucially important ones. [2] Read how interactions work. Iron can cause serious harm in overdose, [3] and zinc has upper limits (see the zinc guide), so do not give a child a supplement without advice from a clinician or pharmacist. Pregnant or breastfeeding people, older adults, and people with kidney, liver, heart or seizure conditions, or planning surgery, should check first. Product contents vary; see quality testing. NCCIH advises discussing any complementary approach for ADHD with the health care provider of the person or child. [2]
References
- National Institute of Mental Health, Attention-Deficit/Hyperactivity Disorder (ADHD). Read 2026-10-23.
- NCCIH, Attention-Deficit Hyperactivity Disorder at a Glance (page last updated May 2019). Read 2026-10-23.
- Elliott SD et al. J Neuropsychiatry Clin Neurosci 2024. Iron Supplementation in Management of Neurodevelopmental Disorders: Systematic Review, Meta-Analysis, and Qualitative Synthesis. Read 2026-10-23.
- NICE, Attention deficit hyperactivity disorder: diagnosis and management (NG87), UK guideline published 14 March 2018, last updated 13 September 2019. Read 2026-10-23.
- Gillies D et al. Cochrane Database Syst Rev 2023. Polyunsaturated fatty acids (PUFA) for attention deficit hyperactivity disorder (ADHD) in children and adolescents. Read 2026-10-23.
- Cooper RE et al. J Psychopharmacol 2015. Omega-3 polyunsaturated fatty acid supplementation and cognition: A systematic review and meta-analysis. Read 2026-10-23.
- Talib M et al. Can J Psychiatry 2024. The Role of Dietary Patterns and Nutritional Supplements in the Management of Mental Disorders in Children and Adolescents: An Umbrella Review of Meta-Analyses. Read 2026-10-23.
- Talebi S et al. Crit Rev Food Sci Nutr 2022. The effect of zinc supplementation in children with attention deficit hyperactivity disorder: a systematic review and dose-response meta-analysis of randomized clinical trials. Read 2026-10-23.
- Fiani D et al. Neurosci Biobehav Rev 2025. Psychiatric and cognitive outcomes of iron supplementation in non-anemic children, adolescents, and menstruating adults: a meta-analysis and systematic review. Read 2026-10-23.
- Abhishek F et al. Cureus 2024. Dietary Interventions and Supplements for Managing Attention-Deficit/Hyperactivity Disorder (ADHD): A Systematic Review of Efficacy and Recommendations. Read 2026-10-23.
- Kucuksahin NG et al. Hum Psychopharmacol 2026. The Impact of Citicoline/Phosphatidylserine Supplementation on Cognitive Performance and Executive Functions in Mental Disorders: A Systematic Review of Controlled Trials. Read 2026-10-23.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.