Is obesity a disease?—the evolving concepts, cancer paradox and association with improved cancer immunotherapy efficacy

Obesity represents a growing health problem in the United States and worldwide, with a prevalence that has doubled since 1980 (1). In the United States, 70% of adults and 37% of adolescents are overweight or obese. The chronic health implications of obesity make it a public health issue with significant economic ramifications. By promoting an altered whole-body physiology, obesity increases the risk for chronic diseases including diabetes, cardiovascular disease, and cancer (2).