[Comment] Brazil's health tax at a crossroads: safeguarding the constitutional victory against ultra-processed foods

Brazil faces a watershed moment for its public health policy. In 2023, the country achieved a constitutional milestone by instituting a Selective Tax to discourage the consumption of products detrimental to health and the environment.1 As Latin America's largest nation, with over 212 million inhabitants, Brazil's health policies exert considerable influence both regionally and globally. Yet this historic advance faces a constant risk of erosion from legislative manoeuvres driven by corporate interests, a conflict that epitomises the global tension between evidence-informed policymaking and the aggressive commercial determinants of health.