Defining obesity as a disease

Whether obesity should be declared as a disease is controversial.1, 2, 3, 4 Very recently, the World Obesity Federation argued that ‘obesity was considered as a chronic, relapsing, progressive, disease process’ that requires intervention.4 By contrast, although the biological basis of obesity (e.g. so-called obesity genes, biology of fat cells) and pathological changes associated with the disease process have been characterized, obesity was not declared as a disease because there is no scientifically applicable definition of a disease.3 Taking a public health point of view, many authorities again argued in favor of obesity as a non-communicable disease resulting from environmental drivers and host responses.5 Finally, considering the benefits and harms arising from declaring obesity as a disease (i.e. taking an utilitarian point of view) also gave evidence to declare obesity as a disease.3 It was assumed that the disease label would provide more benefits than harms to the general population, e.g. by the provision of more resources for novel and effective prevention and treatment of obesity.4 There is however no evidence for the latter idea, i.e. the utilitarian approach is speculative.