Any athlete who has had the unfortunate experience of trying to compete while fighting a cold knows how detrimental a stuffy nose or cough can be to performance. Yet, with kids heading back to school and the fall weather amongst us, cold season is officially here. One of the most popular methods of avoiding a cold includes the age old remedy of popping a vitamin C supplement. Is there any truth to this tactic or is it just plain old fiction?

Vitamin C is a water soluble vitamin. This means that extra vitamin C is not stored in the body but lost through urine. Vitamin C plays many important roles, including:

  • Growth and repair of bones, teeth, skin and other tissues
  • Absorbing iron from plant based foods
  • Protecting cells from damage
  • Keeping the immune system healthy

Males over 19 years of age require 90 mg of vitamin C each day and females, 75 mg each day. Fruits and vegetables are by far the best sources of vitamin C. If you are eating enough fruits and vegetables, then you’re probably getting enough vitamin C. Some of the best food sources include:


Portion: Vitamin C:
Red and yellow pepper ½ cup 140 mg
Orange 1 medium 90 mg
Broccoli, cooked ½ cup 55 mg
Brussel sprouts 4 sprouts 50 mg
Strawberries ½ cup 50 mg
Pineapple ½ cup 50 mg
Mango ½ fruit 40 mg


To be honest, when I started researching for this blog, I thought that I was going to go my regular route of being anti-supplement and pro-food. However, I surprised myself. Research suggests that taking a vitamin C supplement right when you feel a cold coming on and throughout the duration of the cold, could reduce both the severity of symptoms and duration of a cold by about 1-2 days. However, while acute vitamin C supplementation may help reduce the severity and duration of a cold, the research does not support chronic vitamin C supplementation to reduce the number of colds caught per year. In addition, high doses of vitamin C supplements can cause digestive issues such as diarrhea and kidney stones. If you feel a cold coming on, consider taking a 1000 mg vitamin C supplement per day until the cold is gone.

While there may be benefits to short-term vitamin C supplementation, taking vitamin C supplements chronically is not a good idea. Chronic vitamin C supplementation can negatively interfere with training adaptations because it is an antioxidant. When we exercise, we produce free radicals and oxidative stress. Antioxidants help combat these free radicals from being formed. While originally it was thought that free radicals were only bad, they’re actually an important apart of adapting to exercise. These free radicals send signals to our body to adapt to the higher training. If we’re supplementing with a high level of antioxidants, we prevent these free radicals from forming and might not get all the positive training effects.

While you should consider taking a vitamin C supplement when you feel a cold coming on, your best bet for meeting your daily vitamin C requirements is eating a diet rich in fruits and vegetables. It’s better to get our vitamins through natural food sources since food provides so many positive elements that can’t be found in a single pill form such as other vitamins and minerals, fibre, phytochemical or flavonoids. Just remember, your best bet for preventing a cold in the first place is general overall good nutrition, washing your hands and getting enough sleep.

Categories: Megan Kuikman

Megan Kuikman

Hello! I’m Megan Kuikman. I’m a Registered Dietitian with specialized training in sports nutrition. My goal is to help athletes and active individuals achieve a healthy attitude towards health, training, and food. I empower athletes to fuel properly for training in order to restore their health and enhance performance. You can get in touch with me at:


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