Immediate action needed to tackle global obesity in children and adolescent

April 2025

Latest data from the Global Burden of Disease Study 2021 highlight a global epidemic of obesity in children and adolescents. Forecasting data indicate that about one-third of children and adolescents will be overweight or obese by 2050, unless immediate urgent action is taken now.  

GBD 2021 Adolescent BMI Collaborators. Global, regional, and national prevalence of child and adolescent overweight and obesity, 1990–2021, with forecasts to 2050: a forecasting study for the Global Burden of Disease Study 2021. Lancet 2025; 405: 785–812

STUDY SUMMARY

Objective

1) To provide a comprehensive analysis of global, regional, and national trends in the prevalence of obesity and overweight in children, adolescents and young adults (up to 24 years) from 1990 to 2021 using data from the Global Burden of Disease Study 2021

2) To forecast future trajectories to 2050 based on these data. 

Study design

Leveraged data from the Global Burden of Disease Study 

Study population 

Global Burden of Diseases, Injuries, and Risk Factors Study 2021

Main study variable

Overweight and obesity were defined using body mass index (BMI). For adolescents aged 18–24 years, overweight was defined as a BMI between 25.0 kg/m² and <30.0 kg/m², and obesity was defined as a BMI of 30.0 kg/m² or higher. For children and adolescents aged 5–17 years, these classifications were based on the International Obesity Task Force criteria.

Methods

Primary data for models included 1321 measured and self-reported anthropometric data sources from 180 countries and territories derived from survey microdata, reports, and published literature. 

Age-standardized prevalence of overweight, obesity, and overweight and obesity combined in children and adolescents aged 5–24 years from 1990 to 2021 was analyzed. Prevalence was stratified in 5-year age brackets (5–9, 10–14, 15–19, and 20–24 years) and by sex. These data were used to forecast trends from 2030 to 2050.

Key results
  • In 2021, 493 million young people, 18.1% (95% uncertainty interval [UI] 17.5–18.7) aged 5–14 years and 20.3% (19.7–21.0) aged 15–24 years, were overweight or obese. This represents a doubling of prevalence since 1990. Importantly, the global prevalence of obesity tripled from 1990 to 2021, from 2.0% to 6.8%, with 174 million children and adolescents affected in 2021.
  • The increase in the prevalence of obesity was especially rapid in nNrth Africa and the Middle East between 2010 and 2021, resulting in these regions having the highest prevalence of overweight and obesity in 2021. 
  • If current trends continue, forecasting data indicate that globally, 746 million – or about one-third – of children and adolescents will be overweight or obese by 2050, of whom 50% or 360 million will be obese. Given the increase in populations, transition to obesity is forecast to be greatest in North Africa, the Middle East, Latin America and the Caribbean. These regions will account for one-third of the global population of children and adolescents with obesity in 2050. 

Author conclusions

Both overweight and obesity increased substantially in every world region between 1990 and 2021, suggesting that current approaches to curbing increases in overweight and obesity have failed a generation of children and adolescents. Beyond 2021, increases in obesity are expected to continue for all populations in all world regions. Because substantial change is forecast to occur between 2022 and 2030, immediate actions are needed to address this public health crisis.

Comment

The global epidemic of obesity and overweight in childhood and adolescence is the most challenging public health issue for the 21st century. As shown by these data from the Global Burden of Disease Study 2021, childhood obesity is not just problematic for higher income countries, but even more so for lower- and middle-income regions, which show the highest prevalence (notably, North Africa and the Middle East) and the greatest increases (southeast Asia, East Asia, and Oceania). If these trajectories continue, 360 million children and adolescents will be living the consequences of obesity by 2050, with lower- and middle-income countries increasingly bearing more of this burden. 

Beyond the effects on the individuals and their families, the socioeconomic impact of this obesity epidemic in the young is important, with costs to social and healthcare systems predicted to exceed 3 trillion US dollars per year by 2030 (1).  Furthermore, as being overweight or obese as a child has been shown to persist to adulthood, this poses a greater risk of earlier onset of adverse outcomes in later life (2-4), which in turn will impact the burden to society. 

As obesity is one of the foremost preventable risks to health, urgent and immediate action is needed to counter these predictions. This should include national surveillance of obesity in children and adolescents, together with aggressive and targeted measures to transform the diet and lifestyle of all children. In lower- and middle-income regions these also need to take account of the realities of public healthcare for sustainability. Commitment from all stakeholders is critical to achieving change. 

References

  1. Okunogbe et al. Economic impacts of overweight and obesity.  2nd Edition with Estimates for 161 Countries. World Obesity Federation, 2022. 
  2. Simmonds M, Llewellyn A, Owen CG, Woolacott. Predicting adult obesity from childhood obesity: a systematic review and meta-analysis. Obes Rev 2016;17:95-107. 
  3. Baker JL, Olsen LW, Sørensen TI.  Childhood body-mass index and the risk of coronary heart disease in adulthood. N Engl J Med 2007;357:2329-37. 
  4. Park MH, Falconer C, Viner RM, Kinra S. The impact of childhood obesity on morbidity and mortality in adulthood: a systematic review. Obes Rev 2012;13:985-1000. 

Key words: Global Burden of Disease Study; overweight; obesity; children; adolescents; global