Comprehensive Intervention to Promote Healthy Lifestyles and Prevent Cardiometabolic Diseases in Low-Income School Children From Mexico: Protocol for the ESCOLARISANO Randomized Controlled Trial

Background: Obesity is a serious public health issue affecting children in a progressively alarming manner; thus, nutrition education and behavior change interventions during childhood are a priority. Eating and physical activity behaviors are mainly influenced by the environment; therefore, lifestyle changes are often successful when interventions are implemented in places such as the home and school. Schools are fundamental for ensuring the development of students' personalities, skills, abilities, and long-term behaviors. Objective: This study aims to measure the effect of an intervention designed for low-income Mexican schoolchildren, focused on promoting healthy lifestyles for the prevention of obesity and cardiometabolic diseases. Methods: The study design is a randomized clinical trial (NCT05945862), with intervention groups paired with control groups of the same grade. Four elementary schools were selected based on district socioeconomic status. The study will be carried out for 1 year in four phases: (1) initial measurements, including anthropometry, blood pressure, psychosocial diagnosis, family medical history, and behavior variables, such as nutrition knowledge, dietary intake, sleep time and quality, and physical activity; (2) intervention implementation based on social cognitive theory, the behavior change wheel with the capability, opportunity, and motivation influencing behavior theoretical framework, and the transtheoretical theory, covering topics related to nutrition and healthy eating, child health, personal and sleep hygiene, physical activity, psychosocial well-being, and motivation; (3) postintervention measurements, including initial and behavioral measurements and intervention indicators; and (4) 6-month postintervention evaluation using the same initial and behavioral measures as in phase 1. Baseline differences by age, sex, socioeconomic status, and location will be analyzed using chi-square tests (qualitative variables) and analysis of covariance (quantitative variables). Multiple linear regression will test potential baseline associations between dependent variables (anthropometrics and blood pressure) and independent variables (diet, exercise, sleep time, family interaction, psychosocial well-being, and perception of childhood obesity). For comparing changes between the intervention and control groups at postintervention and at 6-month postintervention in anthropometrics, blood pressure, and behavioral variables, we will use multilevel mixed-effects regression models, given the hierarchical structure of participants nested within schools and the repeated measurements over time. SPSS and STATA software will be used with a significance level of P<.05. Results: From October 2023 to August 2024, a total of 451 participants were recruited from 4 different elementary schools in Sonora, México. As of February 2026, the data collected are in the process of being captured and analyzed. Conclusions: The protocol is a comprehensive program designed for schoolchildren in Mexico, intended to be an effective strategy for promoting healthy lifestyles and preventing cardiometabolic diseases. It is important to continuously adapt the intervention before implementation and to evaluate it to ensure its sustainability and expand its impact on other elementary schools, improving the health and well-being of schoolchildren.