Obesity in children and adolescents is a global public health concern, with significant implications for physical, mental, and social well-being. The weight children carry in early childhood determines their trajectory toward obesity, with their body mass index (BMI) during childhood continuing to influence them as they move through adolescence and into adulthood. The causes of childhood and teenage obesity are intricate and varied, making prevention and treatment challenging for doctors and researchers. The increasing incidence of childhood obesity has also led to the early emergence of obesity-associated diseases, including type 2 diabetes, hypertension, dyslipidemia, non-alcoholic fatty liver disease, and psychological issues such as depression and low self-esteem. By assessing BMI annually and providing families with age-appropriate anticipatory advice, pediatricians and family medicine doctors can contribute significantly to the fight against obesity. This comprehensive review discusses prevalence, causes, health consequences, and evidence-based interventions to address this critical issue. It explores the complex interplay of genetic, environmental, and behavioral factors contributing to the rise in childhood and adolescent obesity, underscoring the need for a multifaceted approach to prevention and treatment. Strategies must involve actions at the community and environmental levels, in addition to individual and parental efforts.