摘要：We summarized the data related to foods high in saturated fat and risk of mortality. We searched Cochrane Library, MEDLINE, EMBASE, and ProQuest for studies from January 1952 to May 2012. We identified 26 publications with individual dietary data and all-cause, total cancer, or cardiovascular mortality as endpoints. Pooled relative risk estimates demonstrated that high intakes of milk, cheese, yogurt, and butter were not associated with a significantly increased risk of mortality compared with low intakes. High intakes of meat and processed meat were significantly associated with an increased risk of mortality but were associated with a decreased risk in a subanalysis of Asian studies. The overall quality of studies was variable. Associations varied by food group and population. This may be because of factors outside saturated fat content of individual foods. There is an ongoing need for improvement in assessment tools and methods that investigate food sources of saturated fat and mortality to inform dietary guidelines. National dietary guidelines typically promote foods low in saturated fat. 1–3 These guidelines have arisen from early epidemiological studies showing that increased serum cholesterol was associated with increased risk of cardiovascular disease (CVD) and feeding studies showing that some, but not all, saturated fats increased serum cholesterol in comparison with unsaturated fats. 4,5 However, the effects of diet on CVD can be mediated through pathways other than total serum cholesterol or low-density lipoprotein cholesterol, 6 and the use of intermediate measures such as cholesterol as outcomes could be misleading. Restriction of saturated fat is now being questioned, 7 with a recent meta-analysis showing that intake of saturated fats was not significantly associated with an increased risk of CVD. 8 As awareness of the relationship between diet, nutrition, and health increases in the general public, it is imperative that the dietary advice of health professionals be evidence based and reflect current scientific understanding. The recent debate regarding intake of saturated fats and risk of disease highlights 2 important questions for research. 9 First, should dietary nutrients be considered in isolation? People consume foods, not individual nutrients. Thus, the effect of saturated fat needs to be considered in the context of its food sources. Individual saturated fatty acids may have different effects on mortality risk; for example, the type of saturated fat found in dairy products may be protective for chronic disease. 10–13 Second, are individual biological markers sufficient measures of risk compared with clinical endpoints such as mortality, which give a more definitive outcome? We conducted a meta-analysis of cohort studies reporting the relationship between key food groups typically high in saturated fatty acids and mortality in initially healthy adults. We tested the null hypothesis that there would be no significant association of saturated fat sources with all-cause, CVD, or cancer mortality.
