To examine whether physical activity and adiposity modify the increased risk of cancer associated with diabetes.
We prospectively examined the association of diabetes and risk of cancer among 73,726 persons stratified by physical activity and body mass index (BMI). Adjusted hazard ratios (HRs) with 95% confidence intervals (CI) were estimated from Cox regression.
During a median follow-up of 22.0 years, 9572 people were diagnosed with incident cancer. There was no clear association between diabetes and cancer risk in those reporting high levels of physical activity (=2.0h per week) (HR 0.93; 95% CI: 0.70-1.24) or those with a normal weight (BMI