Obesity, a risk factor for cancer and an established problem in high-income countries, is escalating rapidly in low- and middle-income countries, contributing significantly to the noncommunicable disease (NCD) burden. This is largely as a result of urbanization, associated dietary changes and an increasingly sedentary lifestyle. This article will address the significant obesity burden in South Africa, and discuss possible interventions to reduce the burden of this modifiable cancer risk factor, as well as the role of the Cancer Association of South Africa in contributing to this.