NEW DELHI: Nearly 188 million children and adolescents worldwide are living with obesity, the World Health Organization (World Health Organization) has warned, calling childhood obesity one of the fastest-growing public health crises driven by unhealthy diets, aggressive food marketing and environments that push junk food over nutritious meals.In its latest global guidelines on preventing obesity, the WHO says about 390 million children aged 5–19 years are overweight, including 188 million who are obese, putting them at high risk of diabetes, heart disease and other chronic illnesses later in life.The UN health body warns that children today are surrounded by ultra-processed foods high in sugar, salt and fat, widely promoted through television, digital media and even school environments. Such exposure, it says, is shaping lifelong eating habits and fuelling a surge in obesity at younger ages.Calling for urgent action, the WHO urges governments to restrict marketing of unhealthy foods to children, improve the nutritional quality of food sold in and around schools, and ensure clear front-of-pack warning labels to help families make informed choices. It also stresses the need for healthier school meals, safe drinking water and regular physical activity as part of daily routines.The guidelines caution that obesity is no longer a problem limited to rich countries. Rates are rising sharply in low- and middle-income nations, where children face a double burden of poor nutrition and easy access to cheap, unhealthy food.Without strong policy intervention, the WHO warns, childhood obesity will continue to climb, placing a heavy long-term burden on health systems and cutting into future productivity. Preventing obesity early, it says, is far easier — and far cheaper — than treating lifelong disease.