(Reuters) - The number of obese children and adolescents worldwide has jumped tenfold in the past 40 years and the rise is accelerating in low- and middle-income countries, especially in Asia, a major study said this week.  '

Childhood and teen obesity rates have leveled off in the United States, north-western Europe and other rich countries, but remain “unacceptably high” there, researchers at Imperial College London and the World Health Organization (WHO) said.  

“Over 40 years we have gone from about 11 million to a more than tenfold increase to over 120 million obese children and adolescents throughout the world,” lead author Majid Ezzati of Imperial’s School of Public Health, told a news conference. 

 
This means that nearly 8 percent of boys and nearly 6 percent of girls worldwide were obese in 2016, against less than one percent for both sexes in 1975.  

An additional 213 million children aged 5-19 were overweight last year, but fell below the threshold for obesity, according to the largest ever study, based on height and weight measurements of 129 million people.  

The researchers called for better nutrition at home and at school, and more physical exercise to prevent a generation from becoming adults at greater risk of diabetes, heart disease and cancers due to excessive weight.  

Clear food labels on salt, sugar and fat content are needed to help consumers make “healthy choices”, the study said.  

Taxation and tough restrictions on marketing of junk food should be considered, it said. WHO has already recommended a 20 percent tax on sugary drinks to reduce consumption.