The study, which coincided with World Obesity Day this week (11 October), analysed weight and height measurements from 31.5 million people aged 5 to 19 years, and found obesity rates increased from less than 1 per cent in 1975 to nearly 6 per cent in girls and nearly 8 per cent in boys in 2016. The number of obese 5-19-year-olds rose from 11 million in 1975 to 124 million in 2016.
Lead author Professor Majid Ezzati said: "These worrying trends reflect the impact of food marketing and policies across the globe, with healthy nutritious foods too expensive for poor families and communities. The trend predicts a generation of children and adolescents growing up obese and also malnourished. We need ways to make healthy, nutritious food more available at home and school, especially in poor families and communities, and regulations and taxes to protect children from unhealthy foods."