|Abstract: Zinc ion availability and the common cold (UNESCO - ISTERH 98)|
Solution Zn2+ ions from zinc lozenges are known to have antirhinoviral, primary T-cell lymphocyte immunoregulatory, cell membrane stabilization and other beneficial effects that reduce duration and severity of common colds and terminate incipient common colds. Measures of zinc lozenge efficacy are Zinc Ion Availability (ZIA) values. A biologically closed electric circuit (BCEC) transports orally introduced Zn2+ ions to infected nasal tissues. Conversely, nasally administered Zn2+ ions are repelled by the same BCEC. ZIA factors are salivary concentration of Zn2+ ions at physiologic pH 7.4 and oral contact time. Different zinc compounds release different amounts of Zn2+ ions at physiologic pH accounting for major variations in clinical trial results from 1984 to 1996. Positive, zero and negative ZIA values correlate directly with efficacy. ZIA 100 lozenges reduced duration of common colds by 7 days. ZIA 0 lozenges had no effect. ZIA -55 lozenges increased duration of colds by 4.4 days. Negatively charged zinc species at physiologic pH 7.4 bind with Zn2+ ions released from nasal tissue mast cells during inflammation inducing local immunosuppression. Zinc acetate releases essentially all zinc as Zn2+ ions. Zinc acetate in candy base lozenges has no taste other than astringency. Mast cell granule derived zinc ions are the foundation of the primary immune system. Astonishing improvement in many diseases from restoration of thymic function and regrowth occur when therapeutic doses of zinc (2 mg zinc/kg body weight) are administered daily for several months. Multi gram oral doses of zinc for a few days can terminate life threatening conditions resultant from cytotolytic agents ranging from viruses to toxins. The Journal of Trace Elements in Experimental Medicine, Volume 11, Number 4, 1998, pages 364-365.