Levels of evidence for the association between different food groups/items consumption and the risk of various cancer sites: an umbrella review

This study aimed to determine the level of evidence on the association between food groups/items consumption and the risk of different cancer sites from the meta-analyses/pooled analyses of observational studies. A systematic search was executed in Scopus, PubMed/MEDLINE, and Web of Science. The criteria from the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Expert Report were adopted for evidence grading. In summary, there was convincing evidence for the association between fibre intake and decreased risk of colon and breast cancer. Also, consumption of dairy products, milk, fruits, and fibre was associated with a probable decreased risk of breast cancer. Consumption of whole grains, dairy products, milk, fruits, vegetables, and fibre had a probable inverse association with the incidence risk of gastrointestinal tract cancers. More qualified studies are needed to find reliable findings on the association between various food groups/items consumption and the risk of different cancer sites.

本研究旨在通过观察性研究的荟萃分析（meta-analyses）与汇总分析（pooled analyses），明确食物群组/食物摄入与不同部位癌症风险之间关联的证据等级。研究团队在Scopus、PubMed/MEDLINE及Web of Science数据库中开展了系统检索。本研究采用世界癌症研究基金会/美国癌症研究所（WCRF/AICR）专家报告中的标准进行证据分级。综合分析结果显示，膳食纤维摄入与结肠癌、乳腺癌风险降低存在令人信服的关联。此外，乳制品、牛奶、水果及膳食纤维的摄入，与乳腺癌风险降低存在大概率关联。全谷物、乳制品、牛奶、水果、蔬菜及膳食纤维的摄入，与胃肠道癌症的发病风险呈大概率负相关。未来仍需开展更多高质量研究，以明确各类食物群组/食物摄入与不同部位癌症风险之间的可靠关联。