Despite the popular belief that vitamin C can cure the common cold, the scientific evidence for this is conflicting
. A few studies
have suggested that taking vitamin C supplements when you are exposed to a cold virus or when you first have symptoms can shorten a
cold or even prevent one. Other research has shown that vitamin C supplementation has no impact on a cold's severity or length, but it
can significantly reduce how often a person catches a cold.
Vitamin C may only be useful in case of a cold if you have low levels
of this nutrient to begin with. The likelihood of success may be
very individual -- some people improve, while others do not.
People with kidney disease should avoid vitamin C supplements. Most experts advise that you meet your daily vitamin and mineral
requirements by eating a balanced diet. Taking more than 500 mg of vitamin C at any one time provides no advantage. More than that
amount is simply lost through non-absorption or urination.
- "Colds and vitamin C"