What does public health ethics tell (or not tell) us about intervening in non-communicable diseases?

Obesity has been described as pandemic and a public health crisis. It has been argued that concerted research efforts are needed to enhance our understanding and develop effective interventions for the complex and multiple dimensions of the health challenges posed by obesity. This would provide a secure evidence base in order to justify clinical interventions and public policy. This paper critically examines these claims through the examination of models of public health and public health ethics. I argue that the concept of an effective public health intervention is unclear and underdeveloped and, as a consequence, normative frameworks reliant on meeting the effectiveness criterion may miss morally salient dimensions of the problems. I conclude by arguing for the need to consider both an ecological model of public health and inclusion of a critical public health ethics perspective for an adequate account of the public health challenges posed by obesity.