Abstract
BACKGROUND: In Latin America and the Caribbean (LAC), diets are increasingly dominated by ultra-processed products (UPPs). Although public health policies aimed at reducing UPPs consumption show promise, these are often undermined by corporate influence. Understanding how countries respond to this influence is essential for strengthening food policy development in LAC. OBJECTIVE: Examine how different sectors (government, academia, and civil society organizations) respond to corporate influence throughout the public policy cycle and analyze the key determinants that enable or constrain industry power across six analytical environments in five LAC countries, with the aim of informing actionable policy directions. METHODS: The study follows two sequential and complementary components: (1) policy mapping conducted to assess the progress of six health, food, and nutrition policies within the policy cycle in LAC countries, and (2) a qualitative component consisting of in-depth interviews with key informants from Guatemala, Paraguay, Argentina, Jamaica and Barbados; conducted between May 2024 and May 2025. Data analysis followed a constant comparative approach to identify cross-cutting patterns and context-specific insights. RESULTS: Policy progress varies substantially across food policies and countries. For example, taxation on sugar-sweetened beverages is generally advanced, while marketing restrictions on unhealthy products remain at earlier stages. Regarding the qualitative component, fifteen informants were interviewed; Argentina and academia were the most represented. Based on informants´ responses, corporate strategies and counterstrategies were identified and classified into six environments, each comprising determinants that either constrain corporate power or hinder efforts to address it. These encompassed: (1) political and governance processes; (2) legal and regulatory frameworks, as evidenced in Argentina and Jamaica; (3) narrative and communication strategies leveraging media; (4) knowledge production and dissemination characterized by misleading or suppressed information; (5) advocacy efforts, notably observed in Argentina and the Caribbean; and (6) a cross-cutting, cross-sectoral collaboration to present a unified response to corporate influence. CONCLUSION: Findings indicate that the UPPs industry operates across multiple environments and is shaped by country-specific contexts. Nevertheless, promising responses include transparency and conflict-of-interest mechanisms, strengthened civil society advocacy, and cross-sectoral collaboration to counter corporate influence. These strategies require adaptation to national and local conditions. CLINICAL TRIAL NUMBER: Not applicable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12992-026-01198-9.