Water Consumption during a School Day and Children's Short-Term Cognitive Performance: The CogniDROP Randomized Intervention Trial

• Published in: Nutrients 2020-05, Vol.12 (5), p.1297
• Main Authors: Drozdowska, Alina, Falkenstein, Michael, Jendrusch, Gernot, Platen, Petra, Luecke, Thomas, Kersting, Mathilde, Jansen, Kathrin
• Format: Article
• Language: English
• Subjects: Child; Child Nutritional Physiological Phenomena - physiology; Children; Cognition & reasoning; Cognitive ability; Cognitive tasks; Color; Correlation analysis; Drinking - physiology; Drinking behavior; Drinking water; Executive function; Executive Function - physiology; Exercise - physiology; Female; Fluids; Germany; Humans; Hydration; Laboratories; Male; Memory; Memory tasks; Memory, Short-Term - physiology; Physical activity; Physiology; Randomization; Schools; Short term; Short term memory; Thirst; Urine; Water consumption; Water intake; Water intakes
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu12051297

There is still little research examining the relationship between water consumption in school and specific cognitive performance. The aim of this cluster-randomized intervention CogniDROP trial was to investigate the short-term effects of drinking water during the morning on executive functions. The participants were from the 5 and 6 grade of a comprehensive school in Germany (14 classes, = 250, 61.6% boys). The classes were randomly divided into an intervention group (an education on healthy drinking behavior and a promotion of water consumption) and a control group. A battery of computerized tasks (Switch Task, 2-Back Task, Corsi Block-Tapping Task and Flanker Task) was used to test executive functions. Urine color and thirst were evaluated to check the hydration level. Physical activity over the past 24 h was measured using GT3X ActiGraph. A non-linear relationship was observed between the amount of drinking water and executive performance. Consuming water up to 1000 mL (or up to 50% of Total Water Intake) had benefits during memory tasks. Urine color and number of steps on the study day correlated with water consumed. The results suggest that a water-friendly environment supports school-aged children in adequate water intake resulting in better cognitive performance, especially short-term memory.