Ward J A
Royal South Sydney Hospital, Zetland, New South Wales, Australia.
Drugs Aging. 1998 Mar;12(3):169-75. doi: 10.2165/00002512-199812030-00001.
The hypothesis that oxidative damage due to free radicals is an important cause of aging is the subject of much research and even more interest among the public and lay media. An increasing number of older people are asking whether they should be taking antioxidant vitamins, despite their considerable cost. Epidemiological and laboratory evidence indicates that oxidative damage caused by oxygen free radicals is important in many of the major diseases of older age. It is also clear that a diet high in antioxidants protects against these diseases, including many cancers and ischaemic heart disease. However, it has not been proven whether antioxidant vitamins, taken as dietary supplements, provide the same level of protection as a diet that is rich in fruit and vegetables. Although there appears to be no reason to discourage older people from taking vitamin E (tocopherols) and ascorbic acid (vitamin C), the best advice to give them is to reduce their intake of xenobiotics, to drink tea instead of coffee, and to eat liberal amounts of fruit, vegetables, nuts, soya beans and lentils. The use of beta-carotene as a dietary supplement should be discouraged.
自由基导致的氧化损伤是衰老的一个重要原因,这一假说受到了大量研究,在公众和大众媒体中更是备受关注。尽管价格不菲,但越来越多的老年人在问自己是否应该服用抗氧化维生素。流行病学和实验室证据表明,氧自由基造成的氧化损伤在许多老年主要疾病中都很重要。同样清楚的是,富含抗氧化剂的饮食能预防这些疾病,包括许多癌症和缺血性心脏病。然而,作为膳食补充剂服用的抗氧化维生素是否能提供与富含水果和蔬菜的饮食相同程度的保护,尚未得到证实。虽然似乎没有理由劝阻老年人服用维生素E(生育酚)和抗坏血酸(维生素C),但给他们的最佳建议是减少外源性物质的摄入,改喝茶而不是咖啡,多吃水果、蔬菜、坚果、大豆和扁豆。应不鼓励将β-胡萝卜素用作膳食补充剂。