Zinc and the common cold

A recent Cochrane review of 15 randomised double-blind placebo-controlled trials (1360 participants) found a significant reduction of duration and severity of the common cold in healthy people when zinc supplements were administered within 24 hours of onset of cold symptoms.1 These trials were conducted in upper-middle and high-income countries, where zinc deficiency is uncommon. The review also found zinc taken daily for at least five months in children, reduced the incidence of colds, school absenteeism and prescription of antibiotics.