The common cold is due to a viral infection of the upper respiratory system. It is characterized by a runny nose, nasal congestion, and sneezing that lasts approximately one week. The average person has four to six colds per year. A 2011 review found that zinc can reduce the duration and incidence of the common cold.
Zinc is an essential mineral. It plays roles in immune function, wound healing, eye health, and the synthesis of protein and DNA. Previous research demonstrates that zinc inhibits the replication of cold viruses.
The review drew on data from 13 randomized double-blind, placebo-controlled trials that provided zinc for at least five consecutive days as a therapy for colds and two trials that provided zinc for at least five months as a measure to prevent colds. More than 1,300 people were involved in the various studies.
The authors of the review found a great deal of heterogeneity in the findings of the studies. They attributed this to differences in the nature of the different zinc formulations and dose range, the timing of the intervention (ranging from 24 to 48 hours), and characteristics of the study population (children versus adults). However, they concluded that zinc (as lozenges or syrup) reduced the duration and symptoms of a cold in otherwise healthy people when given at the onset of symptoms. When given for at least five months, zinc also reduced the incidence of colds by 37 percent.
The science digest is a special email we send out just twice per month to members of our premium community. It covers in-depth science on familiar FoundMyFitness related topics.
If you're interested in trying out a few issues for free, enter your email below or click here to learn more about the benefits of premium membership here.