Abstract
Pacific Island Countries (PICs) are located in highly productive fishing regions that supply nutrient‐rich fish to global markets. Marine fisheries are a critical source of protein and essential micronutrients for billions of people worldwide, supporting both local diets and global food security. International trade shapes modern blue food systems, influencing broader distributions and availability of these ‘blue nutrients’. Yet, the structure of these trade networks, the nutritional composition of exported fisheries, and the implications for local food security remain poorly understood. Using global marine fisheries trade data from 1996 to 2020 combined with species‐level nutrient compositions, we analysed production, consumption and nutrient balances for 12 PICs and used network analysis to characterise the structure of international blue nutrient flows. Here we show that many PICs experience persistent net losses of essential nutrients, particularly vitamin B12, protein and fatty acids. This results in nutrient yields far below population needs, with only a few PICs (Vanuatu and Kiribati) meeting average requirements. Compared to global fisheries trade networks, regional PICs trade is more fragmented and less mutually connected, relying on a small number of intermediary countries (Papua New Guinea and Fiji). Despite high domestic production and consumption, 54% of blue nutrients are exported from PICs rather than retained locally, leaving local nutritional deficits unaddressed even as PICs supply global seafood markets. Combining trade, nutrient and network analyses can help inform strategies to increase nutrient retention, strengthen food security and support resilience for PICs in the modern blue food economy.