Original sentence: A report by Eric Konofal and others (Archives of Pediatric and Adolescent Medicine 158, 1113-1115, 2004) showed that blood levels of the iron-binding protein, ferritin, were 50% lower in ADHD subjects than in controls, and that iron supplementation may improve symptoms of ADHD.One interesting hypothesis is that ADHD may be aggrevated by a deficiency in brain iron, an element that modulates dopamine synthesis and dopamine receptor abundance in the brain