Obesity has outpaced undernourishment to become the leading form of malnutrition worldwide for the first time among children and teenagers, according to UNICEF. The United Nations children's agency stated in a report released on Tuesday that nearly one in 10 children aged five to 19 is living with the chronic disease. The epidemic is being fuelled by easy availability of ultra-processed foods even in countries still grappling with child undernutrition and aggressive marketing.