  Citation: Rodríguez-Cortés, F.J.; Morales-Cané, I.; Rodríguez-Muñoz, P.M.; Cappadona, R.; De Giorgi, A.; Manfredini, R.; Rodríguez-Borrego, M.A.; Fabbian, F.; López-Soto, P.J. Individual Circadian Preference, Eating Disorders and Obesity in Children and Adolescents: A Dangerous Liaison? A Systematic Review and a Meta-Analysis. Children 2022, 9, 167. https:// doi.org/10.3390/children9020167 Academic Editor: José Ignacio Baile Ayensa Received: 31 December 2021 Accepted: 27 January 2022 Published: 28 January 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). children Systematic Review Individual Circadian Preference, Eating Disorders and Obesity in Children and Adolescents: A Dangerous Liaison? A Systematic Review and a Meta-Analysis Francisco José Rodríguez-Cortés 1,2,3 , Ignacio Morales-Cané 1,2,3 , Pedro Manuel Rodríguez-Muñoz 1,4 , Rosaria Cappadona 5 , Alfredo De Giorgi 6 , Roberto Manfredini 5,6,7, * , María Aurora Rodríguez-Borrego 1,2,3 , Fabio Fabbian 5,6, * and Pablo JesúsLópez-Soto 1,2,3 1 Department of Nursing, Instituto Maimónides de Investigación Biomédica de Córdoba, 14005 Cordoba, Spain; francisco.rodriguez@imibic.org (F.J.R.-C.); n82mocai@uco.es (I.M.-C.); pedromrodriguez@usal.es (P.M.R.-M.); en1robom@uco.es (M.A.R.-B.); pablo.lopez@imibic.org (P.J.L.-S.) 2 Department of Nursing, Pharmacology and Physiotherapy, Universidad de Córdoba, 14004 Cordoba, Spain 3 Department of Nursing, Hospital Universitario Reina Sofía de Córdoba, 14004 Cordoba, Spain 4 Department of Nursing and Physiotherapy, Universidad de Salamanca, 37007 Salamanca, Spain 5 Department of Medical Science, University of Ferrara, 44121 Ferrara, Italy; rosaria.cappadona@unife.it 6 Clinica Medica Unit, Azienda Ospedaliero-Universitaria ‘S.Anna’, 44121 Ferrara, Italy; degiorgialfredo@libero.it 7 University Center for Studies on Gender Medicine, University of Ferrara, 44121 Ferrara, Italy * Correspondence: roberto.manfredini@unife.it (R.M.); fabio.fabbian@unife.it (F.F.) Abstract: Background: Obesity and other eating disorders are an actual public health problem, especially in childhood and adolescents, and could be also related with chronotype. The aim of this systematic review was to determine the relationship between eating disorders, obesity and the different chronotypes in children and adolescents. Methods: A systematic review of observational studies evaluating young populations dealing with and evaluating chronotype was conducted. Electronic searches were performed in six international databases. A qualitative thematic-categorical analysis was carried out and a random-effects model was used for the quantitative analysis (meta- analysis). Results: Fifteen studies were included, but quantitative analysis was only carried out in three of them. Children and adolescents with an evening chronotype had higher body mass index, consumed more junk food or were more predisposed to suffer from food addiction and night eating syndrome. Conclusions: Children and adolescents with evening chronotype had higher tendency to incorrect eating behaviors and were suffering from overweight/obesity. Environment but also lifestyle factors should be considered in the association between chronotype and eating disorders and obesity. Keywords: feeding and eating disorders; obesity; chronobiology; phenomena; chronotype; circadian rhythms; adolescents; children; sex; gender 1. Introduction The behaviors and biological rhythms of each individual are determined by circadian variations associated with the light-dark cycle over a period of about 24 h per day [1,2]. Possible individual differences in circadian attitudes are called ‘chronotype’. According to Horne and Ostberg, five categories are differentiated: definitely Evening type (E-type), moderately Evening type, neither type or Intermediate (I-type), moderately Morning type (M-type), and definitely Morning type [3,4]. The morning chronotype shows the preference of individuals to wake up early and perform activities early. In contrast, the evening chronotype is found in individuals who wake up late and perform activities in the afternoon. Finally, the intermediate chronotype is found between the two chronotypes [3,5]. Children 2022, 9, 167. https://doi.org/10.3390/children9020167 https://www.mdpi.com/journal/children