How much vitamin C do I need if I have a cold?

Dr. Michael Roizen, MD
Internal Medicine
When you begin to show signs of a cold, increase your vitamin C to as much as 4 grams (4,000 milligrams) a day, taken with plenty of water (eight glasses for 4 grams). Although this won't cure colds, it will lessen the severity of the symptoms. For example, when you have a cold and take your C, you may find that you can keep exercising.

Continue Learning about Vitamin C

Vitamin C Is Not an Exercise Replacement
Vitamin C Is Not an Exercise Replacement
John F. Kennedy once said, “There are risks and costs to a program of action, but they are far less than the long-range risks and costs of comfortable...
Read More
How should I use vitamin C to help my skin look younger?
Dr. Mehmet Oz, MDDr. Mehmet Oz, MD
Taking vitamin C through a supplement or food is beneficial to your health, but to specifically targ...
More Answers
How much vitamin C is safe to take?
Jill A. Grimes, MDJill A. Grimes, MD
The recommended dietary allowance (RDA) for vitamin C is 75 milligrams (mg) for women and 90 mg ...
More Answers
How Can Vitamin C Help Treat Age Spots?
How Can Vitamin C Help Treat Age Spots?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.