Kathrin Jansen1, Jana Tempes2, Alina Drozdowska3, Maike Gutmann3,4, Michael Falkenstein5, Anette E Buyken6, Lars Libuda7, Henrik Rudolf8, Thomas Lücke3, Mathilde Kersting3. 1. Research Department of Child Nutrition, University Children's Hospital, Ruhr University, Bochum, Germany. kathrin.jansen@ruhr-uni-bochum.de. 2. University of Education, Freiburg, Germany. 3. Research Department of Child Nutrition, University Children's Hospital, Ruhr University, Bochum, Germany. 4. Maria-Montessori-Allee 10, 53229, Bonn, Germany. 5. Institute for Work, Learning and Ageing (ALA), Bochum, Germany. 6. Public Health Nutrition, Institute of Nutrition, Consumption and Health, Paderborn University, Paderborn, Germany. 7. Department of Child and Adolescent Psychiatry, University Hospital Essen, University of Duisburg-Essen, Essen, Germany. 8. Department of Medical Informatics, Biometry and Epidemiology, Ruhr-University Bochum, Bochum, Germany.
Abstract
BACKGROUND: Intervention studies suggest an influence of breakfast dietary glycemic index (GI) on children's cognition. The Cognition Intervention Study Dortmund-GI-I study examined whether lunch dietary GI might have short-term effects on selected cognitive parameters. METHODS: A randomized crossover study was performed at a comprehensive school on 2 test days. One hundred and eighty-nine participants (5th and 6th grade) were randomly assigned to one of the two sequences, medium-high GI (m-hGI) or high-medium GI (h-mGI), following block randomization. In the first period, one group received a dish containing hGI rice (GI: 86) ad libitum, the other mGI rice (GI: 62)-1 week later, in the second period, vice versa. Tonic alertness, task switching, and working memory updating were tested with a computerized test battery 45 min after beginning of lunch break. Treatment effects were estimated using the t test for normally distributed data or the Wilcoxon rank-sum test for non-normally distributed data. RESULTS: The crossover approach revealed no effects of lunch dietary GI on the tested cognitive parameters in the early afternoon. However, we determined carryover effects for two parameters, and therefore analyzed only data of the first period. The reaction time of the two-back task (working memory updating) was faster (p = 0.001) and the count of commission errors in the alertness task was lower (p = 0.04) in the hGI group. CONCLUSION: No evidence of short-term effects of lunch dietary GI on cognition of schoolchildren was found. Potential positive effects on single parameters of working memory updating and tonic alertness favoring hGI rice need to be verified.
RCT Entities:
BACKGROUND: Intervention studies suggest an influence of breakfast dietary glycemic index (GI) on children's cognition. The Cognition Intervention Study Dortmund-GI-I study examined whether lunch dietary GI might have short-term effects on selected cognitive parameters. METHODS: A randomized crossover study was performed at a comprehensive school on 2 test days. One hundred and eighty-nine participants (5th and 6th grade) were randomly assigned to one of the two sequences, medium-high GI (m-hGI) or high-medium GI (h-mGI), following block randomization. In the first period, one group received a dish containing hGI rice (GI: 86) ad libitum, the other mGI rice (GI: 62)-1 week later, in the second period, vice versa. Tonic alertness, task switching, and working memory updating were tested with a computerized test battery 45 min after beginning of lunch break. Treatment effects were estimated using the t test for normally distributed data or the Wilcoxon rank-sum test for non-normally distributed data. RESULTS: The crossover approach revealed no effects of lunch dietary GI on the tested cognitive parameters in the early afternoon. However, we determined carryover effects for two parameters, and therefore analyzed only data of the first period. The reaction time of the two-back task (working memory updating) was faster (p = 0.001) and the count of commission errors in the alertness task was lower (p = 0.04) in the hGI group. CONCLUSION: No evidence of short-term effects of lunch dietary GI on cognition of schoolchildren was found. Potential positive effects on single parameters of working memory updating and tonic alertness favoring hGI rice need to be verified.
Authors: Anne Schlegtendal; Lynn Eitner; Michael Falkenstein; Anna Hoffmann; Thomas Lücke; Kathrin Sinningen; Folke Brinkmann Journal: Children (Basel) Date: 2022-01-11