Family-Based Nutrition Intervention to Prevent Overweight and Obesity in School-Age Children.

Inclusion Criteria: * Families of children between 5 and 9 years old. * Children without any medical or nutritional treatment for obesity. * Children classified as normal weight, overweight, or obese based on WHO (Z-score: height for age and BMI for age). * Offspring of mothers aged between 18 and 45 years at delivery. * Term infants from normoevolutive pregnancies without maternal comorbidities. * Families who have a cell phone with internet access and an installed camera. Exclusion Criteria: * Children who are currently suffering from a pathology that requires medication or special treatment * Mothers/Fathers/Guardians who are currently suffering from a pathology that requires medication or special treatment. * Children who have a physical/mental impairment to perform physical activities. * Children from surrogate mothers who have presented at least 2 of the 11 DSM-5 criteria for substance use disorder (alcohol, tobacco, cannabis, or other illegal drugs) before or during the participating child's gestation. * Children from multiple pregnancies. * Parents who do not own a smartphone compatible with the app will be excluded from this study (i.e., version 5.0 or higher for Android).