Vitamin C has been studied extensively during the past 60 years, but the results have been mixed with respect to the common cold.
A new review of clinical trials from the Cochrane Collaboration (an international health information sharing organisation) suggests that vitamin C may, in fact, help reduce your symptoms, even if it doesn’t prevent the sniffles entirely.
What Witamin C Does
Vitamin C provides antioxidant activity to protect the cells in your immune system. A systematic review of 29 high-quality clinical trials that covered more than 11,000 people, found that while regularly taking at least 200 mg of vitamin C each day didn’t keep most people from catching a cold, it appeared to reduce the severity of illness and shorten its duration by several days. This benefit is nothing to be sneezed at!
But if you experience extreme physical stress, as marathon runners and skiers do, taking vitamin C as a preventive agent can reduce the actual incidence of colds by as much as 50 per cent.
However, once symptoms start, adding high doses of vitamin C appears to provide little or no benefit.
Dietary Sources
Since vitamin C is not stored in the body in large amounts, you need to include rich sources in your daily diet. Think fruits and vegetables, because grains, milk and meat products provide very little. The recommended dietary intake of vitamin C is 45 mg for adults daily. Smokers need at least 35 mg more.
The chart below gives the amount of vitamin C in several fruits and vegetables.
| Food Source | Vitamin C (mg) |
| Guava, 1 | 206 |
| Small papaya | 94 |
| Kiwifruit, 1 Large | 84 |
| Orange | 70 |
| Red Cabbage, raw, 1 Cup | 54 |
| Broccoli, cooked, 1/2 Cup | 54 |
