Vitamin C: The Nobel Prize Winner's Legacy and the Truth Behind the Cold Cure
The idea that vitamin C can cure the common cold has been a popular belief for decades, thanks in large part to the work of Nobel Prize winner Linus Pauling. But how did this idea come to be, and is there any truth to it? In this article, we'll explore the history of vitamin C and colds, the science behind it, and the current research on its effectiveness.
The Birth of a Myth
Pauling's book, published in 1970, was a groundbreaking work that sparked a revolution in the way people thought about vitamin C. He claimed that high doses of vitamin C could prevent and treat the common cold, and his recommendations for daily intake were around 1,000-2,000 milligrams. This was a significant departure from the recommended daily intake of just 45 milligrams for adults in Australia, and it sent vitamin C sales soaring.
The Science Behind the Claim
Pauling's claims were initially based on a single placebo-controlled trial in children on a ski camp in the Swiss Alps. He then analyzed four additional studies, but his interpretation of these studies has been widely criticized. The mathematical analyses were incorrect, the studies were of poor quality, and the overemphasis on the study in children was misleading. As a result, many scientists have questioned the validity of Pauling's claims.
The Truth About Vitamin C and Colds
The short answer is that vitamin C does not cure the common cold. Multiple studies have shown that if there is an effect of vitamin C on colds, it is minimal. Even then, any marginal benefits are only under certain circumstances, such as if you're an athlete or in the army. A meta-analysis of ten placebo-controlled trials found that people who took vitamin C had a 15% reduction in severe cold symptoms compared to those who didn't take it, but this was expressed as the number of days confined indoors, which the authors acknowledged as a limitation.
The Bottom Line
Pauling's original advice is over-stated. There is no evidence that vitamin C will reduce your risk of catching a cold. However, there is some evidence that it will reduce how long severe symptoms last, but on average only by about 10%. This means that if severe symptoms from a cold last for five days, it will reduce severe symptoms by about 12 hours. If the severe symptoms last for 24 hours, they will reduce by about two-and-a-half hours.
The Risks of High Doses
Taking high doses of vitamin C (over 1,000 milligrams a day) continually can increase your risk of adverse events, such as gastrointestinal effects, more oxalate excretion, an increase in iron absorption, and interactions with radiation therapy, chemotherapy, and the cholesterol-lowering drugs statins. If you feel you would benefit from vitamin C supplements, discuss this with your GP and limit the dose to below 1,000 milligrams a day.
The Takeaway
While vitamin C may not be a cure-all for the common cold, it is still an important nutrient for overall health. The recommended daily intake for adults in Australia is 45 milligrams, which can be found in foods like half an orange, three to four florets of cooked broccoli, or one-third of a glass of orange juice. Taking vitamin C supplements should be done with caution and under the guidance of a healthcare professional.
