Vitamin C has been in the public eye for a long time. Even before its discovery in 1932, nutrition experts recognized that something in citrus fruits could prevent scurvy, a disease that killed as many as two million sailors between 1500 and 1800. (1) In the 1970s, Chemistry and Peace Nobel laureate Linus Pauling promoted daily megadoses of vitamin C (the amount in 12 to 24 oranges) as a way to prevent colds and some chronic diseases.
There’s no question that vitamin C plays a role in controlling infections. It’s also a powerful antioxidant that can neutralize harmful free radicals, and it helps make collagen, a tissue needed for healthy bones, teeth, gums, and blood vessels. (2) The question is, do you need lots of vitamin C to keep you healthy?
No. Vitamin C’s cold-fighting potential certainly hasn’t panned out. Small trials suggest that the amount of vitamin C in a typical multivitamin taken at the start of a cold might ease symptoms, but for the average person, there’s no evidence that megadoses make a difference, or that they prevent colds. (3) Studies of vitamin C supplements and heart disease, cancer, and eye diseases such as cataract and macular degeneration also show no clear patterns.
2.Institute of Medicine. Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. Washington, DC: National Academy Press, 2000.
3.Douglas RM, Hemila H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2007:CD000980.
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