Does Extra Vitamin C Help When Your Kid Has a Cold?
Vitamin C is pretty important. From 1500-1800, an estimated two million sailors died of scurvy, a nasty disease caused by lack of adequate vitamin C in the diet. It leads to weakness, changes to the gums and skin, soreness in the limbs, and eventually death from bleeding or infections. In 1747, James Lind, a Scottish surgeon who sailed with the Royal Navy, performed one of the first controlled experiments in the history of medicine (1). He took some scurvy-ridden sailors and divided them into different groups. He gave one group daily doses of citrus and the other groups random things from sea water to sulfuric acid (yikes!). Only the sailors who got citrus recovered. Now scurvy is quite rare and limited mostly to refugees, alcoholics, or those with very restricted diets.
Vitamin C’s reputation as a wonder-vitamin is still going strong, however. Parents often tell me proudly how they give their kids larger doses of vitamin C at the start of their colds – and they usually get better! Imagine that! Where did vitamin C’s reputation for boosting your immune system and fighting off colds come from?
Linus Pauling was a stud scientist. He is considered one of the founders of quantum chemistry and also made crucial advances in understanding sickle cell disease. In fact he’s the only scientist who has ever won two unshared Nobel Prizes. As he got older, however, his scientific method began to crumble as he evolved from scientist to guru. He started taking megadoses of vitamin C and claimed to feel healthier and more energetic (a shocking disregard of the placebo effect). He shared his beliefs in a 1970 book titled Vitamin C and the Common Cold. When a Nobel Prize winner tells people they will be healthier and live longer if they take 3000 mg of vitamin C a day, they listen. Vitamin C sales soared, and until his death in 1994 Pauling continued to proselytize that supplements could eliminate the common cold, cure HIV and other diseases, and allow people to live at least twenty-five years longer! (It probably didn’t help that he actually did live really long, until age ninety-three.)
While it’s true that being deficient in vitamin C might impair your immune system, multiple studies have failed to show any benefit for larger doses. And megadoses can cause cramping, diarrhea, and perhaps even kidney stones.
Yet you can go to any pharmacy or corner store and find “Emergen-C” and plenty of other vitamin C supplements claiming to boost your immune system. You and I want to believe that something will help our colds. Colds are no fun. But your immune system is boss and will fight it off anyway. Notice that every one of these packages says in small print, “This product is not intended to diagnose, treat, cure, or prevent any disease.” They’re telling you it doesn’t work. Believe them.
1. Lind, James (1753). A Treatise on the Scurvy. London: A. Millar.