Vitamin–mineral treatment of attention-deficit hyperactivity disorder in adults: double-blind randomised placebo-controlled trial

Double-blind, randomized, placebo-controlled trial in adults with ADHD in Canterbury, New Zealand. Participants in the active arm were medication-free for at least 4 weeks before enrollment; many had comorbid psychiatric disorders. The micronutrient group included 42 participants in a 1:1 allocation with placebo.

EMPowerplus, a broad-spectrum micronutrient formula containing vitamins and minerals, was taken orally at 15 capsules per day in three doses of 5 capsules with food and water for 8 weeks. The placebo was identical in appearance and contained a small amount of riboflavin to mimic smell and urine colour.

Broad-spectrum micronutrient treatment showed preliminary benefit for adult ADHD symptoms over 8 weeks and was generally well tolerated. CAARS DSM-IV ADHD symptoms improved in the micronutrient group on self-report (79.4 to 67.3, p=0.009) and observer report (69.5 to 61.4, p=0.026), and clinician-rated CGI-I-ADHD also favored treatment (2.8 to 2.83, p=0.020). Overall impression improved and functioning improved on GAF (58.7 to 64.5, p=0.045), while MADRS was not significant (17.2 to 11.5, p=0.078) and LIFE-RIFT was not significant (10.5 to 11.6, p=0.292). There were no group differences in adverse events, though prolactin increased in the micronutrient group (P=0.006).

The active arm was small (n=42) and treatment lasted only 8 weeks, which limits precision and long-term interpretation. Participants were recruited from one region and many had psychiatric comorbidity, so generalizability to broader adult ADHD populations is limited. Earthquakes during the enrollment period may also have affected some participants and study conditions.