The association between obesity and academic performance in youth: a systematic review.

Previous studies have found that obesity could influence academic performance. The aim of this study was to systematically review the scientific evidence on the association between obesity and academic performance in school children. A systematic review of English articles was undertaken by using databases PubMed/Medline, ERIC, LILACS, SciELO and Web of Science. Cross-sectional and longitudinal studies examining the association between obesity and academic performance in children and adolescents, published between January 1990 and December 2016, were included. Risk of bias was assessed by using Strengthening the Reporting of Observational Studies in Epidemiology. Thirty-four studies (23 cross-sectional and 11 longitudinal) matched all inclusion criteria and were included. Seven studies were classified as low risk of bias, 23 as medium risk and four as high risk. After controlling for covariates such as socio-economic status, parental education and physical activity, the association between obesity and academic performance becomes uncertain for most of the studies (55.9%). Therefore, at present, there is insufficient evidence to support a direct link between obesity and poor academic performance in school age children. In order to clarify this issue, we need more longitudinal studies with adequate sample sizes and that control for potential confounders.

Physical fitness and academic performance in youth: A systematic review.

Physical fitness (PF) is a construct of health- and skill-related attributes which have been associated with academic performance (AP) in youth. This study aimed to review the scientific evidence on the association among components of PF and AP in children and adolescents. A systematic review of articles using databases PubMed/Medline, ERIC, LILACS, SciELO, and Web of Science was undertaken. Cross-sectional and longitudinal studies examining the association between at least one component of PF and AP in children and adolescents, published between 1990 and June 2016, were included. Independent extraction of articles was carried out by the two authors using predefined data fields. From a total of 45 studies included, 25 report a positive association between components of PF with AP and 20 describe a single association between cardiorespiratory fitness (CRF) and AP. According to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines: 12 were classified as low, 32 as medium risk, and 1 as high risk of bias. Thirty-one studies reported a positive association between AP and CRF, six studies with muscular strength, three studies with flexibility, and seven studies reported a positive association between clustered of PF components and AP. The magnitude of the associations is weak to moderate (ß = 0.10-0.42 and odds = 1.01-4.14). There is strong evidence for a positive association between CRF and cluster of PF with AP in cross-sectional studies; and evidence from longitudinal studies for a positive association between cluster of PF and AP; the relationship between muscular strength and flexibility with AP remains uncertain.