摘要:Objective A meta analysis was conducted to examine the association between the dietary intake of n-3 fatty acids and colorectal cancer risk. Methods Articles published from Jan 1995 to May 2013 were identified through PubMed, EMBASE, CNKI and Cochrane Library database, and relevant references of the included studies were also retrieved. Two authors independently reviewed articles, extracted data and assessed the methodological quality. Meta-analyses were conducted by using STATA 11.0 software. Results A total of 7 case-control studies and 4 prospective cohort studies involving 253 479 participants were included. The pooled relative risks for the highest compared with the lowest n-3 fatty acids dietary intake were 0.88 (95%CI:0.68-1.13;P=0.316, quartiles of intake, 6 studies) and 1.03 (95%CI:0.92-1.16;P=0.606, quintile of intake, 5 studies) for colorectal cancer risk. Conclusions There is insufficient evidence to suggest a significant association between dietary intake of n-3 fatty acids and colorectal cancer incidence. The effect of dietary supplementation with n-3 fatty on colorectal cancer risk needs further investigation.%目的:探讨n-3脂肪酸的膳食摄入量与结直肠癌发生风险的关系。方法计算机检索PubMed、EMBASE、CNKI数据库和Cochrane图书馆已发表的相关研究文献。由2名评价者独立筛选文章、提取数据及评价纳入研究的质量,采用STATA11.0软件完成Meta分析。结果最终共纳入7项病例对照研究和4项前瞻性队列研究,共253479名研究对象。n-3脂肪酸膳食摄入最高量部分的人群相比摄入最低量部分的人群发生结直肠癌的风险是0.88(95%CI:0.68~1.13;P=0.316,4分类,6项研究)和1.03(95%CI:0.92~1.16;P=0.606,5分类,5项研究)。结论 n-3脂肪酸的摄入量与结直肠癌的发生没有显著相关性,膳食摄入n-3脂肪酸与结直肠癌的发生风险之间的关系尚需进一步研究证实。