Carr A C, Frei B
Linus Pauling Institute, Oregon State University, Corvallis 97331, USA.
Am J Clin Nutr. 1999 Jun;69(6):1086-107. doi: 10.1093/ajcn/69.6.1086.
The current recommended dietary allowance (RDA) for vitamin C for adult nonsmoking men and women is 60 mg/d, which is based on a mean requirement of 46 mg/d to prevent the deficiency disease scurvy. However, recent scientific evidence indicates that an increased intake of vitamin C is associated with a reduced risk of chronic diseases such as cancer, cardiovascular disease, and cataract, probably through antioxidant mechanisms. It is likely that the amount of vitamin C required to prevent scurvy is not sufficient to optimally protect against these diseases. Because the RDA is defined as "the average daily dietary intake level that is sufficient to meet the nutrient requirement of nearly all healthy individuals in a group," it is appropriate to reevaluate the RDA for vitamin C. Therefore, we reviewed the biochemical, clinical, and epidemiologic evidence to date for a role of vitamin C in chronic disease prevention. The totality of the reviewed data suggests that an intake of 90-100 mg vitamin C/d is required for optimum reduction of chronic disease risk in nonsmoking men and women. This amount is about twice the amount on which the current RDA for vitamin C is based, suggesting a new RDA of 120 mg vitamin C/d.
目前，成年不吸烟男性和女性维生素C的推荐膳食摄入量（RDA）为60毫克/天，这是基于预防坏血病的平均需求量46毫克/天确定的。然而，最近的科学证据表明，增加维生素C的摄入量可能通过抗氧化机制降低患癌症、心血管疾病和白内障等慢性病的风险。预防坏血病所需的维生素C量可能不足以最佳地预防这些疾病。由于RDA被定义为“足以满足一组中几乎所有健康个体营养需求的平均每日膳食摄入量水平”，因此重新评估维生素C的RDA是合适的。因此，我们回顾了迄今为止关于维生素C在预防慢性病中作用的生化、临床和流行病学证据。综合审查的数据表明，不吸烟的男性和女性每天摄入90 - 100毫克维生素C，可最佳地降低慢性病风险。这个量约为目前维生素C RDA所基于量的两倍，这表明新的维生素C RDA为120毫克/天。
