Skip to Content

Vitamin C and colds


Despite the popular belief that vitamin C can cure the common cold, research about this claim is conflicting.

Large doses of vitamin C may help reduce how long a cold lasts, but they do not appear to protect against getting a cold. This is true even after being exposed to the virus that causes colds.

Taking a vitamin C supplement may help treat a cold only if your body currently has low levels of this vitamin. For example, people who live in cold climates may have low levels of vitamin C, so taking a vitamin C supplement may help keep this group of people from getting colds. This is also true for people who routinely do vigorous exercise, such as running marathons.

The likelihood of success may vary from person to person. Some people improve, while others do not. People with kidney disease should not take vitamin C supplements.

Taking more than 500 milligrams (mg) of vitamin C at any one time is not helpful. More than that amount is simply lost by our body not absorbing it all or through urination.

Most experts advise that you should eat a balanced diet to get your daily vitamin and mineral requirements.


Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2013;1:CD000980. DOI: 10.1002/14651858.CD000980.pub4.

Livingston C, Cozzens J, Hamilton A. Treatments for symptoms of the common cold. Am Fam Phys. 2013;88(3):864C-864D.

Related Images

Review Date: 5/5/2014
Reviewed By: Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2018 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

© Copyright 1997- 2018 A.D.A.M., Inc.