No country has succeeded in reducing obesity rates, resulting in a world where almost a third of the population is overweight or obese, a new analysis finds.

The number of overweight and obese people rose from 857 million in 1980 to 2.1 billion in 2013, researchers said in Thursday’s online issue of The Lancet.

"When we realized that not a single country has had a significant decline in obesity, that tells you how hard a challenge this is," said Christopher Murray of the Institute for Health Metrics and Evaluation at the University of Washington, who led the study.

More than half of the world’s 671 million people who are obese live in 10 countries — the U.S., China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan and Indonesia. The U.S. is home to 13 per cent of the world’s obese individuals.

"Our findings show that increases in the prevalence of overweight and obesity have been substantial, widespread, and have arisen over a short time," Murray and his co-authors concluded.

"Even with aggressive drug therapy, increased rates of overweight and obesity can be expected to have substantial health effects and increase prevalence of diabetes, osteoarthritis, cancers and major vascular disease."

Modernization linked to obesity

Over the last 30 years, the problem has become most acute in the Middle East and North Africa, with more than 58 per cent of adult men and 65 per cent of adult women overweight or obese.

"Modernization has not been good for health," said Syed Shah, an obesity expert at United Arab Emirates University, who found obesity rates have jumped five times in the last 20 years, including in a handful of remote Himalayan villages in Pakistan.

Shah pointed to changes such as the ready availability of a cellphone instead of walking for hours to get to a phone, new roads that bring cheap, fatty, sugary, salty and high-calorie processed food to villagers who no longer rely on food from their farms, and the ubiquitous availability of soft drinks.

For children in developed countries, the prevalence of those overweight and obese has increased from 17 per cent in 1980 to 24 per cent in 2013 for boys and from 16 per cent to 23 per cent for girls.

Last week, the World Health Organization set up a commission to tackle childhood obesity.

"Our children are getting fatter," Dr. Margaret Chan, WHO's director general, said in a speech at the agency's annual meeting in Geneva. "Parts of the world are quite literally eating themselves to death."

The research was funded by the Bill & Melinda Gates Foundation