World Obesity Day: Focus on Sarcopenic Obesity (OS)

Worldwide, 1.9 billion adults suffer from overweight/obesity [1], including 8.5 million French people (17% of the population) according to the national epidemiological survey Obépi-Roche 2020. Faced with this global scourge, in 2016 the United Nations launched the “Decade of Action for Nutrition 2016-2025”, which marks a strong and lasting global commitment to the fight against malnutrition in all its forms (overweight, obesity , malnutrition).

Today, undernutrition and obesity are problems that coexist within the same population mainly because of changes in our lifestyles: modification of our diet with increasingly processed products and reduced physical activity are among the main causes of the development of obesity. Nutrition-related diseases (obesity and malnutrition) lead to a sharp increase in physiological dysfunctions, in particular cardiometabolic and musculoskeletal complications that can be serious.

IHU ICAN teams are conducting numerous research programs to better understand the causes and mechanisms of the onset of cardiometabolic diseases and to develop new approaches to better manage patients. Obesity and nutrition are at the heart of the concerns of doctors and researchers.

What is sarcopenic obesity?

Beyond weight, it is very important to assess the whole body composition of each individual, as it varies according to different body phenotypes. Obesity is an abnormal or excessive accumulation of body fat, but when combined with reduced muscle mass/function, it is referred to as sarcopenic (SO) obesity.

Current research suggests that OS may be associated with a large number of metabolic disorders and an increased risk of mortality, since these two conditions act synergistically [2], [3]. Therefore, OS has attracted increasing interest from the scientific community over the past decades. However, a universally accepted definition of OS is lacking to date, as the majority rely on criteria that consider sarcopenia and obesity separately [4], [5]. It is therefore important to better define OS in order to better manage it because this lack of definition and consistent threshold values constitute a gap in the determination of the precise rates of the prevalence of this disease[6] this has an impact on the prognosis of patients mainly, in individuals with severe obesity, because they not only have a greater quantity of adipose tissue, such as muscle tissue, while body composition is impacted as a whole.

Also, the IHU ICAN teams are carrying out a research project on sarcopenic obesity in order to better characterize it in order to improve its diagnosis and offer personalized care for patients.

This project led by Prof. Jean-Michel Oppert, nutritionist and head of the nutrition/obesity department at the Pitié-Salpêtrière Hospital, by Prof. Vlad Ratziu, gastroenterologist/hepatologist and Vittoria Zambon, researcher and nutritionist , aims to develop a gender-specific (M/F) diagnostic approach for Sarcopenic Obesity for overweight or obese people.

The data of 1427 patients, 42.7% of whom had grade III obesity, were studied: clinical examinations, biochemical analyzes and evaluation of body composition by dual-energy X-ray absorptiometry (DXA).

Once the data was listed, the ICAN I/O platform led by Maharajah PONNAIAH developed a new approach based on AI: unsupervised machine learning.

This innovative new approach will identify body phenotypes at risk for OS, and thus define more effective screening, prevention and intervention measures in the clinical management of this disease, by distinguishing between changes in muscle tissue and fat. A more precise and earlier diagnosis will also make it possible to anticipate the appearance or aggravation of comorbidities possibly associated with OS.


[1] W. World Health Organization and World Obesity Federation, “Obesity and overweight,” 2020.

[2] I. Abete et al., “Association of lifestyle factors and inflammation with sarcopenic obesity: data from the PREDIMED-Plus trial,” J. Cachexia. Sarcopenia Muscle, vol. 10, no. 5, pp. 974–984, 2019, doi: 10.1002/jcsm.12442.

[3] R. A. Bhanji, A. J. Montano-Loza, and K. D. Watt, “Sarcopenia in Cirrhosis: Looking Beyond the Skeletal Muscle Loss to See the Systemic Disease,” Hepatology, vol. 70, no. 6, pp. 2193–2203, Dec. 2019, doi: 10.1002/hep.30686.

[4] T. Cederholm et al., “ESPEN guidelines on definitions and terminology of clinical nutrition,” Clin. Nutr., vol. 36, no. 1, pp. 49–64, Feb. 2017, doi: 10.1016/j.clnu.2016.09.004.

[5] A. J. Cruz-Jentoft et al., “Sarcopenia: Revised European consensus on definition and diagnosis,” Age Ageing, vol. 48, no. 1, pp. 16–31, Jan. 2019, doi: 10.1093/ageing/afy169.

[6] J. A. Batsis and D. T. Villareal, “Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies,” Nat. Rev. Endocrinol., vol. 14, no. 9, pp. 513–537, Sep. 2018, doi: 10.1038/s41574-018-0062-9.