Williamson D F, Pamuk E R
National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia.
Ann Intern Med. 1993 Oct 1;119(7 Pt 2):731-6. doi: 10.7326/0003-4819-119-7_part_2-199310011-00021.
Six published observational epidemiologic studies have reported evidence of reduced mortality rates in persons who have lost weight. In two studies, the reported protective effects of weight loss on mortality could not be justified by the data. In two other studies, weight loss was associated with both increased and decreased longevity in different subgroups. Only one study provided information on whether the weight loss was voluntary, but this study found similar effects of weight loss regardless of volition. These studies provided only limited information on the magnitude of weight loss associated with changes in longevity and no information on the types of methods used to achieve weight loss. Because of difficulties in studying long-term health outcomes related to obesity treatment, randomized, controlled trials are unlikely to provide a practical study design for this issue. Properly designed observational studies will probably provide the most useful information on the effects of voluntary weight loss on longevity.
六项已发表的观察性流行病学研究报告了体重减轻者死亡率降低的证据。在两项研究中，报告的体重减轻对死亡率的保护作用无法由数据证实。在另外两项研究中，体重减轻在不同亚组中与寿命延长和缩短均有关联。只有一项研究提供了关于体重减轻是否为自愿的信息，但该研究发现无论是否自愿，体重减轻的影响相似。这些研究仅提供了与寿命变化相关的体重减轻幅度的有限信息，且未提供关于实现体重减轻所采用方法类型的信息。由于研究与肥胖治疗相关的长期健康结果存在困难，随机对照试验不太可能为该问题提供切实可行的研究设计。设计合理的观察性研究可能会提供关于自愿体重减轻对寿命影响的最有用信息。
