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Vitamin C and cold treatment
Last reviewed: 07.07.2025

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At the first sign of a cold, many people reach for vitamin C supplements. For a long time, it was believed that vitamin C was very good at curing colds. Then came studies that said that vitamin C for treating colds was harmful. Some doctors claim that vitamin C has no effect on colds at all. What is the truth?
What is Vitamin C?
Vitamin C was first recommended for colds in 1970. But despite its widespread use, experts say there is very little evidence that vitamin C actually works to treat colds.
Vitamin C is a vitamin and antioxidant that your body uses to keep you strong and healthy. Vitamin C is used to support the health of your bones, muscles, and blood vessels. Vitamin C also helps form collagen and helps your body absorb iron.
Vitamin C is found in vegetables and fruits, especially oranges and other citrus fruits. This vitamin is also available as a natural dietary supplement in chewable tablets or other forms.
Vitamin C is very good for preventing colds, so we tend to take it in large quantities through foods such as fortified juices, teas and fruits.
Can Vitamin C Prevent or Treat Cold Symptoms?
Vitamin C has been studied for years as a possible treatment for the common cold or as a way to prevent the common cold. But the results have been mixed. Overall, experts have found little benefit from vitamin C in preventing or treating the common cold.
In July 2007, researchers wanted to find out whether taking 200 mg or more of vitamin C daily could reduce the frequency, duration, and severity of colds. After 60 years of clinical research, they found that vitamin C supplements did little to make colds milder or shorter in duration. When vitamin C was taken daily, the duration of colds could be reduced by 8% in adults and 14% in children.
But researchers have found that vitamin C has the greatest impact on people who are exposed to extreme conditions, such as marathon runners. In this group, taking vitamin C cuts the risk of catching a cold in half.
So what does all this mean?
The average adult who suffers from a cold 12 days a year would suffer from one 11 days a year if that person took high doses of vitamin C every day for a year.
For the average child, who suffers about 28 days a year from colds, this means that taking high doses of vitamin C daily will reduce the duration of colds to 24 days a year.
When vitamin C was tested for treating the common cold in 7 separate studies, vitamin C was found to be no more effective than placebo for treating the common cold.
Is vitamin C safe?
Vitamin C can be safely taken from sources such as fruits and vegetables. For most people, vitamin C is safe when taken in recommended amounts. The recommended daily allowance is 90 mg for men and 75 mg for women. High doses of vitamin C (more than 2,000 mg per day for adults) can cause complications such as kidney stones, nausea, and diarrhea.
Taking more than 500 mg of vitamin C at one time will not provide any benefit because the body cannot store it. Also, anyone with kidney disease should avoid vitamin C supplements. If you are unsure about vitamin C dosages for colds, talk to your doctor.
People who benefit most from increased vitamin C are those who are deficient in vitamin C, as well as highly trained athletes and military personnel. Studies conducted with groups of athletes and military personnel who are in very good physical condition and have experience working in extreme conditions have shown that taking vitamin C reduces the risk of catching a cold by 50%. However, these results have not been widely known.
Vitamin C for immunity during colds
If you want to take vitamin C to help your immune system, it's best to get it from foods rather than supplements. Foods high in vitamin C include:
- Citrus fruits and juices
- Green and red peppers
- Strawberry
- Tomatoes
- Broccoli
- Dark green
- Sweet potato and white
- Cantaloupe
- Raspberry, blueberry and cranberry
- Watermelon
- Brussels sprouts
- Pineapple
- Cabbage
So, whether to use vitamin C to treat a cold is up to you and your doctor. In any case, eating fruits and vegetables, as well as vitamin supplements during cold season, will add health to you and your immune system - resistance.
Attention!
To simplify the perception of information, this instruction for use of the drug "Vitamin C and cold treatment" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.