The International Journal of Obesity (abbreviated as IJO) is a peer-reviewed medical journal published by the Nature Publishing Group.

It was established in 1977 as International Journal of Obesity by Newman Pub.

in collaboration with the Association for the Study of Obesity and the North American Association for the Study of Obesity.

In 1992, the journal change its name to International Journal of Obesity and Related Metabolic Disorders upon acquisition by the Nature Publishing Group.

It publishes basic science and clinical studies that address the biochemical, epidemiological, genetical, molecular, metabolic, nutritional, physiological, psychological and sociological aspects of obesity.