Early-Life Strategies for Preventing Obesity in Preschool-aged Children

Kindergarten-Level Inclusion Criteria: * The kindergarten's principal or headmaster consents to participate in the study, and the school demonstrates a high level of cooperation. Required personnel, such as a school health care provider, are available. * The total number of children in the middle and senior classes (approximately ages 4-6) exceeds 100. * Teachers and parents of the selected classes demonstrate good compliance and willingness to cooperate with project implementation. Kindergarten-Level Exclusion Criteria: * Special kindergartens, such as part-time institutions or schools for children with special needs. * Kindergartens that have participated or plan to participate in other obesity-related intervention projects within the past year or upcoming year. * Kindergartens scheduled for closure or relocation within the next two years. Child-Level Inclusion Criteria: * The child's primary caregivers can proficiently use smart phones. * The child is expected to remain enrolled in the same kindergarten for at least one year. * Parents or legal guardians provide written informed consent for participation. Child-Level Exclusion Criteria: * Obesity caused by genetic disorders, endocrine diseases, central nervous system damage, or long-term medication use. * History of significant diseases affecting major organs such as the heart, lungs, liver, or kidneys (e.g., congenital heart disease, hypertension, asthma). * Children on special diets, including vegetarianism. * Children diagnosed with pathological eating disorders or conditions that impair physical activity.