Obesity should be defined as a chronic disease, the World Obesity Federation has said.

The question of whether obesity should be referred to as a disease has been a topic of contention for many years now. However, the federation has published a statement in the medical journal, Obesity Reviews, confirming its support for this description.

It said that obesity fits the epidemiological model of a disease process, except that the toxic or pathological agent in this case is diet-related rather than a microbe (a microorganism that causes disease, such as bacteria).

The statement was prepared by a scientific committee of the federation and according to one of its authors, US obesity expert, Dr George Bray, accepting the concept that obesity is a chronic disease ‘is important for several reasons'.

"First, it removes the feeling that patients alone are responsible for their excess weight. It also focuses attention on the ways in which this disease process can be tackled. And finally, it shows that if we can successfully treat obesity, many of its associated diseases will be eliminated," he said.

Meanwhile, in an accompanying letter to the editor of Obesity Reviews, the federation's policy experts said that declaring obesity a disease could benefit those affected who want access to medical advice and support.

They pointed out that obesity is a normal response to an obesogenic environment, but is not in itself a biologically normal or healthy condition.

They added that defining obesity as a disease could reduce people's internalised stigma and change public discourse about blame for the condition.