International investment liberalization, transnational corporations and NCD prevention policy non-decisions: a realist review on the political economy of tobacco, alcohol and ultra-processed food.

While ISDS-related regulatory chill is a real risk under certain conditions, international investment-related NCD prevention policy non-decisions driven by broader political economy dynamics may well be more widespread and impactful on NCD regulatory environments. There is therefore a clear need to expand the research agenda on investment liberalization and NCD policy beyond regulatory chill and engage with theories and approaches from international relations and political science, including political economy and power analyses.