Clinical Research Directory

Inclusion Criteria: * The child's primary caregivers can proficiently use smart phones. * Child is expected to remain in the same kindergarten for at least one year. * No use of antibiotics or probiotic supplements, no acute stress events (e.g., trauma or severe infection), gastrointestinal symptoms (e.g., abdominal pain, constipation, diarrhea), or vaccinations within the 3 months prior to stool sample collection. * Parents voluntarily agree to participate in the study and provide written informed consent. Exclusion Criteria: * Obesity caused by genetic factors, diseases (e.g., endocrine disorders, central nervous system damage), or medication use. * History of major organ diseases, including cardiovascular, pulmonary, hepatic, or renal conditions (e.g., heart disease, hypertension, asthma). * Children following special diets (e.g., vegetarians). * Children with pathological eating disorders or medical conditions that limit physical activity.