Is there a relationship between body mass index and academic achievement? A meta-analysis

To date, although there have been several systematic reviews about the relationship between overweight/obesity and academic performance, none of the reviews were conducted quantitatively, thus the extent overweight/obesity is related to academic performance still remains unclear. Thus, the aim of this study was to quantitatively review the scientific evidence on the association between body mass index (BMI) and academic performance. A systematic review of articles examining such relationship was undertaken using four databases, namely, PubMed, Web of Science, EBSCOhost and ProQuest Dissertations & Theses Global. The search period covered the research literature up to July 2017. Data from 60 selected studies (involving 164,049 participants) were extracted and analysed following procedures for meta-analysis. Sixty studies met all inclusion criteria and were included. Using a random-effects meta-analysis model, a weak negative correlation between BMI and academic achievement (r = −.111; 95% confidence interval [CI]: −.155 to −.067; P