For more information about building a healthy dietary pattern, refer to the Dietary Guidelines for Americans and the USDA's MyPlate. Although fruits and vegetables are the best sources of vitamin C, many other foods have small amounts of this nutrient. Thus, through a varied diet, most people should be able to meet the vitamin C RDA or at least obtain enough to prevent scurvy. People who have limited food variety—including some elderly, indigent individuals who prepare their own food; people who abuse alcohol or drugs; food faddists; people with mental illness; and, occasionally, children—might not obtain sufficient vitamin C [ 4, 6-9, 11]. People with malabsorption and certain chronic diseases Knekt P, Ritz J, Pereira MA, O'Reilly EJ, Augustsson K, Fraser GE, et al. Antioxidant vitamins and coronary heart disease risk: a pooled analysis of 9 cohorts. Am J Clin Nutr 2004;80:1508-20. [ PubMed abstract] Table 1 lists the current RDAs for vitamin C [ 8]. The RDAs for vitamin C are based on its known physiological and antioxidant functions in white blood cells and are much higher than the amount required for protection from deficiency [ 4, 8, 11]. For infants from birth to 12 months, the FNB established an AI for vitamin C that is equivalent to the mean intake of vitamin C in healthy, breastfed infants. Table 1: Recommended Dietary Allowances (RDAs) for Vitamin C [ 8] Age Padayatty SJ, Riordan HD, Hewitt SM, Katz A, Hoffer LJ, Levine M. Intravenously administered vitamin C as cancer therapy: three cases. CMAJ 2006;174:937-42. [ PubMed abstract]

Taylor PR, Li B, Dawsey SM, Li JY, Yang CS, Guo W, et al. Prevention of esophageal cancer: the nutrition intervention trials in Linxian, China. Linxian Nutrition Intervention Trials Study Group. Cancer Res 1994;54(7 Suppl):2029s-31s. [ PubMed abstract] Evans JR. Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration. Cochrane Database Syst Rev 2006;(2):CD000254. [ PubMed abstract]Epidemiologic evidence suggests that higher consumption of fruits and vegetables is associated with lower risk of most types of cancer, perhaps, in part, due to their high vitamin C content [ 1, 2]. Vitamin C can limit the formation of carcinogens, such as nitrosamines [ 2, 29], in vivo; modulate immune response [ 2, 4]; and, through its antioxidant function, possibly attenuate oxidative damage that can lead to cancer [ 1]. Hecht SS. Approaches to cancer prevention based on an understanding of N-nitrosamine carcinogenesis. Proc Soc Exp Biol Med 1997;216:181-91. [ PubMed abstract]

Padayatty SJ, Sun H, Wang Y, Riordan HD, Hewitt SM, Katz A, Wesley RA, Levine M. Vitamin C pharmacokinetics: implications for oral and intravenous use. Ann Intern Med 2004;140:533-7. [ PubMed abstract] Lin J, Cook NR, Albert C, Zaharris E, Gaziano JM, Van Denburgh M, et al. Vitamins C and E and beta carotene supplementation and cancer risk: a randomized controlled trial. J Natl Cancer Inst 2009;101:14-23. [ PubMed abstract] Other reported effects of high intakes of vitamin C include reduced vitamin B12 and copper levels, accelerated metabolism or excretion of ascorbic acid, erosion of dental enamel, and allergic responses [ 8]. However, at least some of these conclusions were a consequence of assay artifact, and additional studies have not confirmed these observations [ 8]. Most Popular Products: Butter Bronzer , Eye Booster Ultra-Fine Liquid Eyeliner, Organic Wear Natural Origin, Mascara and the new Diamond Plumper Lip Gloss and All-Star Face Palette,

Benefits

At this time, the evidence is inconsistent on whether dietary vitamin C intake affects cancer risk. Results from most clinical trials suggest that modest vitamin C supplementation alone or with other nutrients offers no benefit in the prevention of cancer. Johnston CS. The antihistamine action of ascorbic acid. Subcell Biochem 1996;25:189-213. [ PubMed abstract] Today, vitamin C deficiency and scurvy are rare in developed countries [ 8]. Overt deficiency symptoms occur only if vitamin C intake falls below approximately 10 mg/day for many weeks [ 5-8, 22, 23]. Vitamin C deficiency is uncommon in developed countries but can still occur in people with limited food variety. Groups at Risk of Vitamin C Inadequacy