Can Vitamin C Help My Cold?

When you're sniffling and sneezing from a cold, you may be tempted to reach for a bottle of vitamin C pills or drink some orange juice. But does vitamin C prevent or treat your symptoms? So far, the evidence is mixed.

What Is It?

Vitamin C is a nutrient your body uses to keep you strong and healthy. It helps maintain your bones, muscles, and blood vessels. It also helps you absorb iron.

You can get vitamin C when you eat fruits and veggies, especially oranges and other citrus fruits. It's also sold as a dietary supplement in the form of pills or chewable tablets.

Can Vitamin C Prevent or Treat Cold Symptoms?

There have been a lot of studies, but the findings aren't consistent. Overall, experts find little to no benefit if you use vitamin C to prevent or treat a cold.

In 2010, researchers looked at all studies and found that taking vitamin C every day did not prevent the number of colds that a person got. In some cases it made symptoms improve. However, vitamin C didn't help if people took it after they showed signs of getting sick.

The results were different for people who were in extremely good physical condition, such as marathon runners. People like that who took vitamin C every day cut their risk of catching a cold in half.

So what does all this mean?

If you take at least 0.2 grams of vitamin C every day, you're not likely to have fewer colds, but they may end a day or two quicker.

Is It Safe?

In general, vitamin C won't harm you if you get it by eating food like fruits and veggies. For most people, it's also OK if you take supplements in the recommended amount.

Higher doses of vitamin C (greater than 2,000 milligrams per day) may cause kidney stones, nausea, and diarrhea.

Talk to your doctor if you're thinking of taking vitamin C pills and let him know about any other dietary supplements you use.

WebMD Medical Reference Reviewed by Neha Pathak, MD on January 17, 2017

Sources

SOURCES:
National Institute of Allergy and Infectious Diseases: "Common Cold."
PubMed: "Intake of Vitamin C and Zinc and Risk of Common Cold: A Cohort Study."
Mayo Clinic: "Cold Remedies: What Works, What Doesn't, What Can't Hurt."
Medscape: "Vitamin C May Be Effective Against Common Cold Primarily in Special Populations."
Douglas, R. The Cochrane Collaboration, issue 3, John Wiley & Sons Ltd., 2007.
Linus Pauling Institute.
UptoDate: "The common cold in adults: Treatment and prevention."

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