Purpose: To present a critical evaluation of the current evidence concerning the therapeutic value of vitamin C for the prophylaxis and treatment of the common cold.
Data sources: Cochrane, PubMed, Natural Standard, and the National Center for Complementary and Alternative Medicine databases were searched to identify and acquire primary research reports, literature reviews, and secondary analyses related to the clinical objective. Published clinical trials, literature reviews, meta-analyses, and systematic reviews were evaluated for evidence-based practice implications.
Conclusions: Vitamin C is frequently used for the treatment and prophylaxis of the common cold; however, no published recommendations were found in a review of the nurse practitioner literature that specifically address the efficacy of vitamin C for the common cold. Our literature review revealed that vitamin C is not effective at preventing the common cold in the general adult population; however, it is effective at preventing colds when consumed regularly by athletes training in subarctic conditions. We also found that regular vitamin C consumption may reduce the duration of cold symptoms in both adults and children, but it does not decrease the severity of cold symptoms.
Implications for practice: NPs should counsel their patients that regular vitamin C consumption may decrease the duration of cold symptoms, but does not affect symptom severity or act as a prophylaxis.