A Global Systematic Review of Health and Environmental Outcomes, Acceptability and Feasibility of Aquatic Foods in School Meals

School meal programmes support children’s food security, health and learning. Aquatic foods, including fish, shellfish and seaweed, provide protein, essential fatty acids and micronutrients, and some have lower environmental impacts than terrestrial animal-source foods. However, evidence on their integration into school meals has not been systematically synthesised. We systematically reviewed peer-reviewed and grey literature in English and Spanish on aquatic foods in school meals. Searches of Web of Science, PubMed, Cochrane Reviews and FAO AGRIS, supplemented by manual searches, identified 1,052 records. Two reviewers independently screened 975 abstracts and 156 full texts. Risk of bias was assessed using tools selected according to study design, and findings were synthesised narratively across nutritional, health, cognitive, acceptability, operational, producer and environmental outcomes. Seventy-three publications from 29 countries met the inclusion criteria. Evidence was concentrated in high-income settings and focused primarily on fish. A small number of independent trials reported improvements in selected nutrient biomarkers and cognitive outcomes, although broader dietary interventions sometimes prevented attribution to aquatic foods alone. Acceptability varied with product form, preparation and familiarity; feasibility depended on cost, procurement, storage and supply chain capacity. Environmental outcomes varied by product, comparator and impact measure. Evidence on producer outcomes, and aquatic foods other than finfish remained limited, details on aquatic food source were rarely included in studies. Aquatic foods can contribute to nutritious and diverse school meals, but effective integration requires attention to nutritional objectives, acceptability, procurement, food safety and environmental performance. Research across diverse settings is needed to identify which aquatic foods, forms and implementation approaches deliver intended benefits. Future studies should assess consumption and nutritional outcomes alongside costs, environmental trade-offs and producer benefits, while reporting species and sourcing to support context-specific policy and programme design.