Obesity: A preventable, treatable, but relapsing disease.

In 2013, the American Medical Association recognized obesity as a disease, of growing scientific, social, and political interest. In 2016 in the United States, prevalence rates of preobesity and obesity exceeded 60%. In Italy, these rates exceeded 40%. Total costs related to excess weight reached 9.3% of the U.S. gross domestic product, whereas in Italy the total annual cost of diabetes alone was estimated at 20.3 billion euros/y. The expansion of adipose tissue and visceral fat causes compression, joint stress, metabolic disorders, organ dysfunction, and increased mortality. The increase in peripheral and central fat mass is a chronic and potentially reversible process with appropriate diagnosis and treatment. Conversely, fattening can turn into a chronic relapsing form, complicated by comorbidities and cardiovascular events. The increased risk for mortality and morbidity also can affect metabolically healthy obese individuals, if the condition is underestimated, with disease progression. Due to its inaccuracy, body mass index must be replaced with body composition for the diagnosis of obesity. The chances of obesity reversibility are closely linked to improving the diagnosis and to timely nutritional interventions. Generalization and stigma hinder the treatment of obese individuals. The recognition of obesity as a disease and institutional interest can shift the focus onto obesity and not on the obese, with improvements in adherence to prevention plans. Anthropogenic factors and gut microbiota can influence human behavior and food choice, such as food addiction. Obesity has all the criteria to be recognized as a disease. Proper clinical management will lead to cost and complications savings, such as in diabetes. The aim of this review was to discuss in detail the criteria for defining primary obesity as a disease in a step-by-step manner.