The first-of-its-kind analysis, published in The Lancet, shows that 2.1 billion people around the world are now classified as being overweight or obese - and that no country has successfully reduced obesity rates in 33 years.
Led by Dr Marie Ng of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, the analysis found that the number of overweight and obese individuals globally increased from 857 million in 1980 to 2.1 billion in 2013.
The team said that such a widespread and rapid rise in global obesity rates over the last three decades is presenting a major public health epidemic in both the developed and the developing world.
"Obesity is an issue affecting people of all ages and incomes, everywhere," said Professor Christopher Murray, director of IHME and senior author of the research. "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."
Over the course of the study, rates of overweight and obesity among adults have increased for both men (from 29% to 37%) and women (from 30% to 38%), said the authors. In developed countries, men had higher rates of overweight and obesity, while women in developing countries also showed higher rates.
Looking at individual countries, Ng and her colleagues revealed that the highest proportion of the world's obese people (13%) live in the United States, while China and India together represent 15% of the global obese population.
Meanwhile, countries in the Middle East and North Africa, Central America, and Island nations in the Pacific and Caribbean have also reached 'exceptionally high' rates of overweight and obesity, with many showing rates at 44% or higher.
In 2013, the highest rates of overweight and obesity were seen in the Middle East and North Africa, where more than 58% of men and 65% of women age 20 or older were found to be either overweight or obese, they said.
In Central America, more than 57% of adult men and more than 65% of adult women were overweight or obese, with the highest prevalence—greater than 50% among men and women—found in Colombia, Costa Rica, and Mexico.
Fatter at a younger age
The team also warned that in many developed countries the peak of obesity rates is moving to younger ages. While among children and adolescents, obesity has increased substantially worldwide.
Between 1980 and 2013, the prevalence of overweight or obese children and adolescents increased by nearly 50%, revealed Ng and her colleagues.
In 2013, more than 22% of girls and nearly 24% of boys living in developed countries were found to be overweight or obese.
And, it isn't just a problem for the developed world. Rates are also on the rise among children and adolescents in the developing world, they said, noting that nearly 13% of boys and more than 13% of girls are overweight or obese.
"The rise in obesity among children is especially troubling in so many low- and middle-income countries," said Ng. "We know that there are severe downstream health effects from childhood obesity, including cardiovascular disease, diabetes, and many cancers."
"We need to be thinking now about how to turn this trend around."
The report also highlights that:
- More than 50% of the world's 671 million obese live in 10 countries: US, China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan, and Indonesia.
- The United Kingdom, US and Australia are among the high-income countries with large gains in obesity among men and women.
- Several countries in the Middle East showed the largest increase in obesity globally. These include Bahrain, Egypt, Saudi Arabia, Oman, and Kuwait.
- In six countries, all in the Middle East and Oceania—Kuwait, Kiribati, the Federated States of Micronesia, Libya, Qatar, and Samoa—the prevalence of obesity for women exceeds 50%.
- In Tonga, both men and women have obesity prevalence over 50%.
- In sub-Saharan Africa, the highest obesity rates (42%) are seen among South African women.
Source: The Lancet
Published online ahead of print, doi: 10.1016/S0140-6736(14)60460-8
"Global, regional, and national prevalence of overweight and obesity in children and adults during 1980–2013: a systematic analysis for the Global Burden of Disease Study 2013"
Authors: Marie Ng, Tom Fleming, Margaret Robinson, et al