Is Vitamin C Effective for Cold Prevention?

Last Updated: February 13, 2024

Cold and flu season is among us, and for many people, this is a time where they turn to vitamin C supplements in an effort to boost their immune system and prevent colds.

But is this practice based on solid scientific evidence, or is it just a popular myth?

Keep reading to find out! 

What is Vitamin C and What Does it Do in the Body?

Vitamin C, also known as ascorbic acid, is an essential nutrient that plays a number of important roles in the body.

It’s an antioxidant that helps to protect cells from oxidative stress and damage, and is also involved in the synthesis of collagen, a protein that helps to form connective tissue in the body and heal wounds.

In addition to these functions, vitamin C is thought to have immune promoting properties. It’s involved in the production and function of immune cells, such as white blood cells and antibodies, which help to defend the body against infections and diseases.

How Much Is Too Much?

Because the body does not make Vitamin C on its own, it is considered an essential nutrient that must be obtained from the diet.

The recommended daily allowance is 75mg per day for women, and 90mg per day for men. People who smoke have lower levels of Vitamin C, which increases their requirements by an additional 35mg per day.

You may notice that some Vitamin C supplements contain much higher amounts than what is recommended (sometimes over 1000% the daily value)! The more you take above what your body needs, the less will be absorbed, and the rest will just be excreted out.

Because it is a water soluble vitamin, the body is unable to store it. Supplementing is generally safe, but taking more than the upper limit of 2000mg can cause gastrointestinal discomfort such as abdominal cramps and diarrhea.

Does Vitamin C Help Prevent Colds?

Regularly taking Vitamin C supplements has not been shown to significantly lower the risk of getting a cold for most people, but it may help to reduce the duration of the cold once you have it- this is only if you are taking a large dose supplement every single day (not just when you are sick).

Beginning to take a supplement after you get sick probably won’t do much to improve symptoms or shorten the duration of your cold. Because of this, it is not recommended to take supplemental Vitamin C to prevent or treat colds.

How To Get Enough Vitamin C Through Diet

Fortunately, getting enough Vitamin C through your diet is simple so long as you are eating enough fruits and vegetables.

Citrus fruits, bell peppers, broccoli, brussels sprouts, tomatoes, kiwi, leafy greens, and strawberries have some of the highest Vitamin C levels per serving.

Having just 1 medium orange and 1/2 cup broccoli will provide more than the recommended daily amount of Vitamin C. By incorporating several servings of fruits and vegetables in your day, you will be getting well over the minimum amount.

Bottom Line

As it turns out, human nutrition is more complex than a single nutrient packaged in a pill to ward off an illness.

While there is no evidence to suggest that high doses of Vitamin C supplements can prevent the cold, it is still important to make sure you are getting enough through food sources.

Start by eating 5 servings of fruits and vegetables per day. These foods will not only provide the recommended amount of Vitamin C, but also other vitamins, minerals, and antioxidants that work together to support your health and immune system.

If you are unsure about your specific needs or worried you may have a deficiency, consult your doctor or a dietitian before taking a supplement. Vitamin C supplements can interact with certain medications, so it’s best to discuss with a health professional before taking one.


Leave a Reply

Your email address will not be published. Required fields are marked *