What is the Connection Between Vitamin C and the Common Cold?

The connection between vitamin C and the common cold has traditionally been a point of debate. Since the 1970s, some proponents have claimed that a high dose of vitamin C can both decrease the chance of a cold virus infecting an individual and lessen the symptoms of an already infected person. Many medical researchers, however, dispute these claims.

Controversy began in 1970 when an American chemist named Linus Pauling published a book claiming that a daily dosage of around 3 grams of vitamin C could combat the common cold virus. The chemist also implied that vitamin C might be helpful in cancer treatments. A leading medical research organization — the Mayo Clinic — conducted clinical studies and concluded that no correlational benefits existed between administration of vitamin C and the common cold. Pauling contented that the studies were marred by the fact that orally administered vitamins were used rather than injectable vitamin C.

Vitamin C is a nutrient that helps facilitate various chemical reactions in the body that sustain life, like cellular respiration, and also helps maintain bone, muscle, and blood vessel structure. While the body makes some vitamin C on its own, it mostly must be supplemented through certain foods like oranges and strawberries, or through pharmaceuticals. Many medical organizations recommend that an individual ingests between 40 milligrams and 2 grams of vitamin C each day.

One proposed function that generated a suspected link between vitamin C and the common cold is the vitamin's bolstering of immune system functions. The immune system fights the spread of invasive viruses or bacteria in the body. Therefore, if a lack of vitamin C adversely affects the immune system, it in turn reduces an individual’s resistance to harmful foreign substances like a cold virus. Nearly all colds begin with exposure to a cold virus, and subsequent infection results in unpleasant symptoms like nasal discharge, stuffy nose, sneezing, and achiness.

Subsequent studies since the 1970s have failed to uncover a connection between intake of vitamin C and the common cold. Researchers also dismiss the notion that vitamin C can reduce the severity of cold symptoms, except in some cases where an individual is in an environment with sustained cold temperatures. Some studies have noted a slight decrease in the length of a cold following vitamin C dosage, however.

Any self-medication, particularly as it relates to vitamin C for colds, should be discussed with a medical professional. High doses of vitamin C can cause side effects such as nausea and diarrhea in some individuals. A doctor can also elaborate on the realistic benefits of vitamin C and the common cold symptom solutions.