Is there a correlation between ADHD and low iron?
What the evidence shows
1) Association: lower ferritin (iron stores) is common in ADHD
Multiple meta-analyses report significantly lower serum ferritin in patients with ADHD than in healthy controls, while serum iron itself is often not different.
Earlier pediatric reports also described a high prevalence of low ferritin among children with ADHD.
Interpretation: ferritin (a marker of iron stores) tends to run lower in ADHD populations, supporting a biological link (iron is required for dopamine synthesis and transporter function), but this alone does not prove causation.
2) Trials of iron supplementation (symptom impact)
Open-label/controlled pediatric data: In children with ADHD and low ferritin, iron supplementation (e.g., ferrous sulfate providing ~80 mg elemental iron/day) was associated with improvement on ADHD rating scales.
Randomized, double-blind adjunct trials: Adding ferrous sulfate to methylphenidate in non-anemic children with ferritin <30 data-preserve-html-node="true" ng/mL reduced ADHD symptoms more than placebo adjunct.
More recent pediatric study: A 2021 clinical trial also reported improvements in Conners’ subscales with iron supplementation.
Interpretation: When iron deficiency/low ferritin is documented, supplementation can modestly improve ADHD symptoms, including as an adjunct to stimulants. Evidence is strongest in children; adult data are limited and mixed. These studies do not establish that iron deficiency causes ADHD, but they support treating documented low ferritin as part of care.
3) Adults and special populations
Some observational work suggests links between iron-deficiency anemia and adult ADHD symptoms, but interventional evidence in adults remains sparse.
Practical, clinical takeaways (evidence-based)
Test before treating.
If ADHD symptoms are present—especially with fatigue, restless sleep, pica, or heavy menses—check ferritin (plus CBC and iron studies).
Ferritin is an acute-phase reactant, so interpret alongside CRP/clinical context. (Meta-analyses emphasize ferritin over serum iron for this reason.)
Who benefits most?
Children with low ferritin (commonly <30 data-preserve-html-node="true" ng/mL) show the clearest response signal to iron repletion in trials.
Role with stimulants;
Small RCTs suggest iron repletion can enhance symptom control when used with methylphenidate in iron-deficient children. This is adjunctive—not a replacement for standard therapy.
Guideline context
Pediatric literature and AAP-affiliated reports have long highlighted the high rate of low ferritin in ADHD and the rationale for assessing iron stores, though universal screening/treatment without deficiency is not recommended.
Bottom line
Correlation: Well supported—ADHD is associated with lower ferritin.
Causation: Unproven.
**Treatment signal **
In iron-deficient pediatric patients, iron supplementation has shown symptom improvements (including as an adjunct to stimulants). Routine iron for normal ferritin is not evidence-based.
