"The results of our meta-analysis showed that oral zinc formulations may shorten the duration of symptoms of the common cold."
"Intake of zinc was associated with a significant reduction in the duration (days) (mean difference (MD) ?1.03, 95% confidence interval (CI) ?1.72 to ?0.34) (P = 0.003) (I2 statistic = 89%) but not the severity of common cold symptoms (MD ?1.06, 95% CI ?2.36 to 0.23) (P = 0.11) (I2 statistic = 84%)."