BACKGROUND: Obesity is a chronic disease that affects millions of adults and children globally. Obesity is particularly prevalent in the US and is associated with adiposity-related complications, such as cardiovascular disease, hypertension, type 2 diabetes, dyslipidemia, obstructive sleep apnea, cancer, and reduced quality of life. The Obesity Medicine Association's 4 pillars of obesity treatment are nutrition therapy, physical activity, behavioral counseling, and medical interventions, the latter of which includes pharmacotherapy, complication management, and bariatric procedures. Long-term obesity treatment using these treatment modalities guides chronic disease management to achieve sustained weight reduction, improved health outcomes, and improved quality of life. METHODS: In this narrative review, we focus on obesity as a chronic disease and the importance of chronic disease management. We also review body composition changes that occur with obesity and the goals of obesity treatment as they relate to body composition. Finally, obesity treatment modalities and recommendations are discussed. RESULTS: Individuals with pre-obesity, which is a state of early obesity, often progress to obesity. Further, individuals with obesity attempting weight reduction frequently reduce weight and experience subsequent weight recurrence, highlighting the chronic nature of obesity. Pathophysiologic factors such as the location and degree of adiposity, as well as the health of adipose tissue, impact the risk factors, outcomes, and treatment options for patients with obesity. Treatment modalities and appointment frequency can be personalized to individualize treatment and maximize adiposity reduction and preservation of lean body mass. CONCLUSIONS: Early and lifelong treatment is critical for maintaining lean body mass as well as preventing weight recurrence and increased adiposity. Obesity treatment should reduce adiposity, preserve lean muscle, and maintain bone health. Weight-reduction maintenance that can be sustained long-term is also a critical component of chronic disease management.