Childhood obesity: WHO draws a new treatment line

Children with obesity under the age of 9 should not be given weight-loss medicines, bariatric surgery or weight-loss devices, while adolescents aged 10-19 could be considered for approved anti-obesity medicines if a supervised programme combining diet, physical activity and behavioural interventions fails to deliver the desired results.
That age-based treatment divide is among the sharpest takeaways from the World Health Organisation’s (WHO’s) new guideline on the integrated management of obesity in children and adolescents – a significant shift from its earlier guidance, which focused more on identifying, preventing and managing excess weight in young children.
The advisory covers kid and adolescents aged 29 days to 19 years.
The new guideline treats obesity as a chronic, relapsing disease that can require long-term, structured care rather than simply telling a child to eat less and exercise more.
The scale of the problem explains the shift. In 2024, an estimated 170 million children and adolescents aged 5-19 were living with obesity, including 70 million children aged 5–9 and 100 million adolescents aged 10-19. Obesity prevalence in this age group has quadrupled since 1990, rising from 2% to 8%.
For India, the issue is particularly complex. The country is dealing with a double burden of malnutrition – undernutrition and micronutrient deficiencies on one side and increasing overweight and obesity on the other.
Rapid changes in diets, greater consumption of energy-dense packaged foods, sedentary lifestyles and longer screen time have made childhood obesity an increasingly important public-health concern.
The WHO does not use the adult definition of obesity – a BMI of 30 or above for children because their bodies are constantly growing and their body composition changes with age and sex.
For children aged 5–19 years, obesity is defined as BMI-for-age more than two standard deviations above the WHO growth-reference median. For children under five, WHO defines obesity as weight-for-height more than three standard deviations above the WHO Child Growth Standards median.
That distinction matters because childhood obesity is not simply about body weight. Excess adiposity during the growing years can increase the risk of type 2 diabetes, cardiovascular disease and other non-communicable diseases later in life. Children can also face bullying, stigma and discrimination because of their weight.
The new WHO guidance therefore moves away from viewing obesity purely as an individual behavioural problem and recognises the influence of biology, genetics, food environments, physical activity, behavior and wider social factors.