¹Division of Nutritional Epidemiology, The National Institute of Environmental Medicine, Karolinska Institutet, PO Box 210, Stockholm SE-17177, Sweden

Correspondence: Dr SC Larsson, E-mail: susanna.larsson@ki.se

Received 13 June 2007; Revised 12 July 2007; Accepted 17 July 2007; Published online 14 August 2007.

Abstract

Cohort studies of excess body weight and risk of liver cancer were identified for a meta-analysis by searching MEDLINE and EMBASE databases from 1966 to June 2007 and the reference lists of retrieved articles. Results from individual studies were combined using a random-effects model. We identified 11 cohort studies, of which seven on overweight (with a total of 5037 cases) and 10 on obesity (with 6042 cases) were suitable for meta-analysis. Compared with persons of normal weight, the summary relative risks of liver cancer were 1.17 (95% confidence interval (CI): 1.02–1.34) for those who were overweight and 1.89 (95% CI: 1.51–2.36) for those who were obese. This meta-analysis finds that excess body weight is associated with an increased risk of liver cancer.