Despite being included in the 1948 World Health Organization’s International Classification of Diseases version 6, the recognition and understanding of obesity as a non-communicable disease entity has only recently come to the fore [1, 2]. With rapid advances in the understanding of the biology of obesity, we are entering a new era of enhanced opportunities for its prevention, treatment, and management. These advances are to the benefit of those at risk of developing obesity and an estimated one billion individuals worldwide living with this disease [3].

In this exciting special issue of the International Journal of Obesity entitled “Obesity: a 100-Year Journey” we are privileged to have insights and perspectives from world-leading expert clinicians and researchers in this area. Beginning with an all-encompassing overview of advances in the understanding of obesity and the important international milestones in the establishment of professional societies, Professor George Bray’s insights are the cornerstone of this issue [4]. It is a privilege to have his contribution to this edition as he is a distinguished obesity scholar and was a founding editor of the International Journal of Obesity in 1976. Professor Bray’s article is an essential read for any student as well as for established obesity practitioners and researchers.

Obesity is an adiposity-based chronic disease that can relapse. Gomez-Ambrosi et al. provide an excellent overview of how the understanding of obesity as a disease has evolved the last 100 years in terms of its definition, assessment, and treatment approaches [5]. Perhaps the time has come to drop the terminology of “obesity” for “obesities” as this better reflects the diversity of the phenotypes. Ghosh and Bouchard provide an insightful perspective on key research gaps and opportunities in the genetics of obesity [6]. They highlight the need for further research into obesity opposing alleles and epigenetic mechanisms, plus the opportunities that bioinformatic advances open for research in this area. Quantification of body composition is critical for the developments in obesity research and practice. Heymsfield provides a thought-provoking overview of key advances across the last 100 years, and how they intersected with advances in radiological and nuclear science, as well as the detrimental effects of war and famine [7].

Fundamental to the treatment of obesity are the essential elements of physical activity and behavioral interventions. Oppert and colleagues discuss the evidence of the impact of exercise on weight loss and provide an insightful suggestion that the conversation needs to be reframed to reflect the broader health benefits of exercise in individuals living with obesity [8]. Chao et al. review and succinctly summarize the evolution of behavioral-based interventions for obesity treatment across the past century [9]. They highlight key challenges in behavioral treatment modalities, which include finding more effective approaches to achieving greater weight loss and long-term weight maintenance. Further, they discuss the future of behavioral obesity treatment and its continued relevance in combination with newer obesity management medications. Tying these ideas together, Ranjibar and colleagues provide a thorough overview of causative factors for obesity that are intrinsic or extrinsic to the individual [10]. With this, they emphasize that a personalized approach is needed to treat and manage obesities.

As highlighted in this issue, our improved understanding of the biology of obesity across the last 100 years means that it is time to move beyond the inaccurate and oversimplified “eat less, move more” approach to its prevention and treatment. Prevention is critical with obvious benefits for individuals and society, but so is treatment. If obesity (or obesities) is successfully treated and managed, then the current health and lives of people living with this disease can be improved. Furthermore, an estimated 200 diseases caused by obesity can potentially be prevented. This is to the benefit of individuals and society in current and future generations.

It has been an absolute pleasure to serve as a Co-editor of this special edition. I am optimistic about the future of obesity research and its incredible potential to translate findings into effective strategies for both preventing obesity and treating obesity, which will improve the current and future health of individuals living with this disease.