The guidance comes as obesity has overtaken underweight as the most common form of malnutrition among school-aged children and adolescents worldwide.
WHO estimates that about 400 million people aged between five and 19 were overweight in 2024, including approximately 170 million living with obesity. The prevalence of obesity within the age group has increased fourfold since 1990.
The organisation recommends that children and adolescents receive tailored nutritional advice, regular physical activity and behavioural programmes involving parents or other caregivers.
For children under 10, WHO does not recommend weight-loss medicines, bariatric surgery or medical devices because of insufficient evidence regarding their long-term safety and effectiveness.
For adolescents aged between 10 and 19, medicines known as GLP-1 drugs may be considered where supervised lifestyle interventions have failed. Bariatric surgery may also be considered for physically and mentally mature adolescents with severe obesity after at least six months of unsuccessful treatment.
The guidance reflects growing debate over the use of medicines such as GLP-1 treatments in younger populations. Several drugs are already approved for certain adolescents in the United States and Europe, but WHO said evidence concerning their long-term use remains limited.
The organisation said sustainable changes in eating habits and physical activity should remain the foundation of obesity care rather than relying primarily on medical intervention.
WHO also highlighted the importance of affordability and access. Healthy diets and opportunities for physical activity need to be available to children across different income groups if governments are to reduce obesity rates at population level.
The rise in childhood obesity is creating wider implications for health systems because excess weight during childhood can increase the risk of chronic conditions later in life.
For governments, schools and healthcare providers, the guidance therefore places greater emphasis on prevention alongside treatment.
WHO's recommendations are expected to influence national health policies as governments attempt to respond to a rapidly changing global pattern of malnutrition in which obesity is increasingly replacing undernutrition as a major public-health challenge.
