Zinc may benefit common cold symptoms

According to a new review, zinc supplements may reduce the severity and duration of symptoms associated with the common cold.

The review of 15 randomized controlled trials found that, after seven days, more patients taking zinc supplements (syrup, lozenges or tablets), taken within 24 hours of the first signs of a cold, had cleared their symptoms compared to placebo (1). When supplemented for at least five months, zinc also reduced cold incidence, school absenteeism and prescription of antibiotics in children.

The researchers commented that the review strengthens the evidence for zinc as a treatment for the common cold. However, it is difficult to make a general recommendation because not enough is known about the optimum dose, formulation or length of treatment. In vitro assays have indicated that zinc possesses antiviral properties, lending biological plausibility to the study results.

The common cold is one of the most widespread illnesses in the world. It is estimated that adults suffer from between two to four episodes annually, while children in school may have 12 episodes per year. There is, however, no proven treatment for the common cold.

1. Singh M. and Das R. R. Zinc for the common cold. The Cochrane Collaboration, Cochrane Database of Systematic Reviews. 2011.