AKK Study in Improving Obesity and Metabolic Status in Children and Adolescents

Inclusion Criteria: * Age range: 7 years old to 18 years old (inclusive of boundary values), gender not restricted. * Primary obesity: According to the WS/T 586-2018 standard issued by the National Health Commission of China, or the internationally recognized CDC/WHO standard, diagnosed as obesity (if BMI ≥ the 95th percentile of children of the same age and gender). * The subjects and their legal guardians understand the research content, voluntarily participate and sign the written informed consent form (for guardians), and the informed consent form (for children aged 8 years and above). * Able to comply with the research protocol, complete all visits and sample collection. Exclusion Criteria: * Have a definite endocrine disorder causing obesity (such as Cushing's syndrome, hypothyroidism), a genetic syndrome (such as Prader-Willi syndrome), or other known organic diseases. * Have a severe primary disease of the liver, kidney, cardiovascular system, respiratory system or hematopoietic system, etc. * Have used antibiotics, probiotics, prebiotics or synbiotic products within 3 months prior to screening. * Have a history of systemic use of glucocorticoids or other drugs that may affect weight and metabolism (such as metformin, systemic glucocorticoids, diuretics, etc.) within 1 month prior to screening. * Subjects are allergic to any component of the study product (AKK probiotic capsules or placebo). * Subjects are participating in other clinical trials. * Have a history of severe gastrointestinal diseases, such as inflammatory bowel disease (IBD). * Other conditions as determined by the researcher to be unsuitable for participation in this study.