Beyond the usual technical and evidentiary considerations, there are ethical questions that we must consider in the justification of our obesity interventions in the name of expected population health gains. These relate to the types of health identities that are permitted in society, the possible unintended consequences of preferencing certain health identities over others, and the manner in which public health policies and interventions are justified. The prevalence of overweight and obesity in Australia highlights some of the areas of uncertainty and identifies some important ethical questions that arise as a result of this uncertainty. I propose that the Australian obesity prevention strategy could be evaluated using the Nuffield Council on Bioethics stewardship model of public health to assess whether any current approaches exceed recommended intervention constraints or limits. My aim is to prompt further debate on this topic.