“Vitamin C can prevent or cure the common cold.”

The enduring belief that large doses of vitamin C can prevent or cure the common cold largely stems from the influential work of Nobel laureate Linus Pauling. In 1970, Pauling published his bestselling book, "Vitamin C and the Common Cold," advocating for megadoses of ascorbic acid to combat respiratory infections. His celebrity status as a highly respected scientist lent immense credibility to his claims, leading to a surge in public interest and a dramatic increase in vitamin C supplement sales during the 1970s.

Despite the widespread popularity ignited by Pauling's assertions, extensive scientific research over decades has not definitively supported the idea that vitamin C prevents colds in the general population. Numerous studies, including comprehensive reviews, consistently show that regular vitamin C supplementation does not reduce the incidence of the common cold for most people. While it is an essential nutrient for overall immune function and health, the human body cannot store large quantities of the vitamin, and excess amounts are typically excreted.

However, some evidence suggests a modest impact in specific scenarios. For instance, daily vitamin C intake might slightly shorten the duration of cold symptoms, by about 8% in adults and 14% to 18% in children, and potentially reduce their severity. A more significant benefit has been observed in individuals undergoing extreme physical stress, such as marathon runners or skiers, where regular supplementation has been shown to halve the risk of catching a cold. Yet, taking vitamin C only after cold symptoms have already begun generally shows no consistent therapeutic effect.

The persistent belief in vitamin C as a cold remedy continues because the idea of a simple, natural solution to a common ailment is appealing. Pauling's initial endorsement, coupled with the general understanding that vitamin C is beneficial for health, created a powerful and lasting misconception. While a balanced diet provides sufficient vitamin C for most individuals and is crucial for overall well-being, relying on large doses to prevent or cure a cold is not supported by the bulk of scientific evidence.