"Who the hell is upstream pushing them all in?" Reclaiming public health's defining metaphor to counter the commercial determinants of health.

Public health policy and practice are often described by means of a metaphor that depicts interventions as "upstream" efforts to prevent people from falling into a river, from which they must be rescued "downstream" by overwhelmed healthcare services. The upstream-downstream metaphor has been described as public health's defining metaphor. We apply a commercial determinants of health lens to re-engage with the initial intentions of McKinlay's seminal 1975 essay from which this metaphor emerged, and to critique its current uses. We examine how the upstream-downstream metaphor has come to be used in ways that depart radically from its original intent, which was to characterise the practices of powerful commercial actors who profit from the production of harm and disease. The subtle but important shift in language from people being pushed, to falling into the river, among other depoliticising processes, contributes to an individualising and victim-blaming approach to health harms, deflecting from the role of commercial power and practices. There is a pressing need to reclaim public health's defining metaphor as part of the wider agenda to address commercial determinants as the major public health challenges of our time.