Educational practices for promoting healthy hydration in primary education in the face of climate change: a systematic review of the literature.

Climate change is increasing children’s exposure to heat and, consequently, their risk of dehydration during their primary school years. Yet hydration education is not consistently embedded in education policy or primary curricula. This systematic review, reported in accordance with PRISMA 2020, examined school-based educational practices designed to promote healthy hydration in Primary Education (6 to 12 years). A search was conducted in the Web of Science Core Collection on January 29th, 2025 for studies published between 2015 and 2024. Two reviewers independently screened records and assessed risk of bias using design-appropriate tools (RoB 2, ROBINS-I, and JBI checklists). Given the substantial heterogeneity in intervention components and outcome indicators, a narrative synthesis was performed. Twelve studies were included, spanning randomized and non-randomized interventions and observational and qualitative or documentary designs across diverse school contexts. Overall, multi-component approaches, particularly those combining improved access to drinking water with classroom-based educational activities and routine supports, were associated with increased water intake, and when measured, improved physiological hydration indicators. Evidence for broader outcomes, including cognitive or academic measures and sustainability-related awareness, was mixed and dependent on the outcome assessed. Risk of bias ranged from low to high; common limitations included reliance on self-reported intake, short intervention duration, limited control for confounding in non-randomized designs, and scarce medium- to long-term follow-up. Future research should prioritize standardized and validated hydration measures, clearer specification of educational strategies, including teacher roles and competencies, and longer follow-up to strengthen the evidence base under climate-related heat risks.