Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies

Excess bodyweight, expressed as increased body-mass index (BMI), is associated with the risk of some common adult cancers. We did a systematic review and meta-analysis to assess the strength of associations between BMI and different sites of cancer and to investigate differences in these associations between sex and ethnic groups.We did electronic searches on Medline and Embase (1966 to November 2007), and searched reports to identify...