Anemia and neutropenia developed in a man who took pharmacologic doses of supplemental zinc. Laboratory investigation showed high zinc level, hypocupremia, low ceruloplasmin level, and ringed sideroblasts. All resolved after withdrawal of zinc. Self-administered zinc appears to have caused severe copper deficiency, with secondary anemia and neutropenia. Physicians should be aware of this deleterious and completely reversible effect of megadose mineral therapy. Zinc ingestion or exposure should be considered in the differential diagnosis of unexplained anemia, leukopenia, or sideroblastic anemia.