The effect of vitamin D and magnesium supplementation on the mental health status of attention-deficit hyperactive children: a randomized controlled trial

Randomized, double-blind, placebo-controlled trial; 66 children with ADHD aged 6–12 years; randomization stratified by gender; inclusion criteria included low serum 25-hydroxyvitamin D (<30 ng/dL) and low serum magnesium (<2.3 mg/dL).

Vitamin D 50,000 IU/week taken with lunch; Magnesium 6 mg/kg/day taken with lunch; duration: 8 weeks.

Serum 25-OH vitamin D and magnesium increased significantly in the vitamin D plus magnesium group versus placebo after 8 weeks. SDQ scores improved in emotional problems, peer problems, total difficulties, and internalizing domains compared with placebo; conduct problems, prosocial behavior, externalizing, and hyperactivity did not show significant changes. Authors conclude that co-supplementation may improve behavioral function and mental health in vitamin D- and magnesium-deficient children with ADHD; larger, well-designed trials are needed.

Combined supplementation prevents isolation of individual nutrient effects; small sample size (n=66); short duration (8 weeks); dietary intake of magnesium and vitamin D not assessed; only deficient participants included; uncertain applicability to non-deficient individuals; no long-term follow-up.