Traditionally associated with an affluent lifestyle, the problem is expanding worldwide, with more than 62 percent of overweight people now in developing nations, said the report.
There are some 2.1 billion overweight or obese people in the world today – up from 857 million 33 years earlier.
Among the most striking statistics: more than half the population of Tonga is now classified as obese – a dangerous level of overweight – as are more than 50 percent of women in Kuwait, Libya, Qatar and Samoa.
The United States also stands out with nearly 75 percent of men and 60 percent of women overweight or obese, according to the Global Burden of Disease Study published in The Lancet medical journal.
“Obesity is an issue affecting people of all ages and incomes, everywhere,” said Christopher Murray, director of the University of Washington Institute for Health Metrics and Evaluation, who helped collate the data for the period 1980 to 2013.
“In the last three decades, not one country has achieved success in reducing obesity rates, and we expect obesity to rise steadily as incomes rise in low and middle-income countries in particular, unless urgent steps are taken to address this public health crisis.”
One is considered overweight with a weight-to-height (BMI) ratio of 25 or over, and obese from 30 upward.
A staggering 671 million people now fall within the obese category, said the study – 78 million of them in the United States, which accounts for five percent of the world’s population, but more than a tenth of its grossly overweight people.
China and India, with much larger populations, trailed 2nd and 3rd in the top 10 obese countries with 46 million and 30 million people respectively, followed by Russia, Brazil, Mexico, Egypt, Germany, Pakistan and Indonesia.
Overweight people are more prone to cardiovascular disease, cancer, diabetes, osteoarthritis and kidney disease, and the soaring numbers are placing a heavy burden on health care systems, said the study.
Excess body weight is estimated to have caused 3.4 million deaths in 2010, and previous research has warned that an unabated rise in obesity could start eating away at life expectancy.
The study, based on data from 188 countries, said the prevalence of obese and overweight adults grew by 28 percent worldwide, and by nearly 50 percent for children.
For men, the increase was from 29 to 37 percent, and for women from 30 to 38 percent of the population.