Nearly one-third of the world's population is obese or overweight, new data show 

This is an image of a weight scale. Credit: CDC/Debora Cartagena

29 may 2014--Today, 2.1 billion people—nearly 30% of the world's population—are either obese or overweight, according to a new, first-of-its kind analysis of trend data from 188 countries. The rise in global obesity rates over the last three decades has been substantial and widespread, presenting a major public health epidemic in both the developed and the developing world.

The study, "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," conducted by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington and published in The Lancet on May 29, found that the number of overweight and obese individuals globally increased from 857 million in 1980 to 2.1 billion in 2013. Overweight is defined as having a Body Mass Index (BMI), or weight-to-height ratio, greater than or equal to 25 and lower than 30, while obesity is defined as having a BMI equal to or greater than 30.

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%). In developed countries, men had higher rates of overweight and obesity, while women in developing countries exhibited higher rates. Also in developed countries, the peak of obesity rates is moving to younger ages.

"Obesity is an issue affecting people of all ages and incomes, everywhere," said Dr. Christopher Murray, director of IHME and a co-founder of the Global Burden of Disease (GBD) study. "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."

Looking at individual countries, the highest proportion of the world's obese people (13%) live in the United States. China and India together represent 15% of the world's obese population. Rates in the study were age-standardized, meaning they were adjusted for differences in population size and ages over time and across countries.

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%. In 2013, more than 22% of girls and nearly 24% of boys living in developed countries were found to be overweight or obese. Rates are also on the rise among children and adolescents in the developing world, where nearly 13% of boys and more than 13% of girls are overweight or obese. Particularly high rates of child and adolescent obesity were seen in Middle Eastern and North African countries, notably among girls.

"The rise in obesity among children is especially troubling in so many low- and middle-income countries," said Marie Ng, Assistant Professor of Global Health at IHME and the paper's lead author. "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."

Regionally, countries in the Middle East and North Africa, Central America, and Island nations in the Pacific and Caribbean have already reached exceptionally high rates of overweight and obesity—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. More than two-thirds of the countries in the region had overweight and obesity rates of over 50% in adult men and women. 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. In the Pacific Islands, nearly 44% of men and more than 51% of women are overweight or obese, as are nearly 38% of men and more than 50% of women in the Caribbean.

While the percentage of people who are either overweight or obese has risen substantially over the last 30 years, there have been marked variations across regions and countries. In developed countries, increases in obesity that began in the 1980s and accelerated from 1992 to 2002 have slowed since 2006. Conversely, in developing countries, where almost two-thirds of the world's obese people currently live, increases are likely to continue.

Key findings:

• More than 50% of the world's 671 million obese live in 10 countries (ranked beginning with the countries with the most obese people): US, China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan, and Indonesia.
• The US, United Kingdom, and Australia are among the high-income countries with large gains in obesity among men and women.
• Over the 33-year period of research, several countries in the Middle East showed the largest increase in obesity globally. These countries 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. Health risks such as cardiovascular disease, cancer, diabetes, osteoarthritis, and chronic kidney disease increase when a person's BMI exceeds 23. In 2010, obesity and overweight were estimated to have caused 3.4 million deaths, most of which were from cardiovascular causes. Research indicates that if left unchecked, the rise in obesity could lead to future declines in life expectancy.

Provided by Institute for Health Metrics and Evaluation

Fighting fat and climate change

By SETH BORENSTEIN, AP Science WriterSun Nov 11, 12:03 PM ET
America's obesity epidemic and global warming might not seem to have much in common. But public health experts suggest people can attack them both by cutting calories and carbon dioxide at the same time.
How? Get out of your car and walk or bike half an hour a day instead of driving. And while you're at it, eat less red meat. That's how Americans can simultaneously save the planet and their health, say doctors and climate scientists.
The payoffs are huge, although unlikely to happen. One numbers-crunching scientist calculates that if all Americans between 10 and 74 walked just half an hour a day instead of driving, they would cut the annual U.S. emissions of carbon dioxide, the chief greenhouse gas, by 64 million tons.
About 6.5 billion gallons of gasoline would be saved. And Americans would also shed more than 3 billion pounds overall, according to these calculations.
The Centers for Disease Control and Prevention is considering public promotion of the "co-benefits" of fighting global warming and obesity-related illnesses through everyday exercise, like walking to school or work, said Dr. Howard Frumkin, director of the CDC's National Center for Environmental Health.
"A simple intervention like walking to school is a climate change intervention, an obesity intervention, a diabetes intervention, a safety intervention," Frumkin told The Associated Press. "That's the sweet spot."
Climate change is a deadly and worsening public health issue, said Frumkin and other experts. The World Health Organization estimated that 160,000 people died in 2000 from malaria, diarrhea, malnutrition and drownings from floods — problems that public health and climate scientists contend were worsened by global warming. Officials predict that in the future those numbers will be higher.
The American Public Health Association, which will highlight the health problems of global warming in April, is seeking to connect obesity and climate change solutions, said executive director Dr. Georges Benjamin.
"This may present the greatest public health opportunity that we've had in a century," said University of Wisconsin health sciences professor Dr. Jonathan Patz, president of the International Association for Ecology and Health.
The key is getting people out of the car, Patz and Frumkin told the public health association at its annual convention. Reducing car travel in favor of biking or walking would not only cut obesity and greenhouse gases, they said, it would also mean less smog, fewer deaths from car crashes, less osteoporosis, and even less depression since exercise helps beat the blues.
In a little-noticed scientific paper in 2005, Paul Higgins, a scientist and policy fellow with the American Meteorological Society, calculated specific savings from adopting federal government recommendations for half an hour a day of exercise instead of driving.
The average person walking half an hour a day would lose about 13 pounds a year. And if everyone did that instead of driving the same distance, the nation would burn a total of 10.5 trillion calories, according to the scientist, formerly with the University of California at Berkeley. At the same time, that would cut carbon dioxide emissions by about the same amount New Mexico produces, he said.
"The real bang for the buck in reducing greenhouse gas emissions was from the avoided health expenses of a sedentary lifestyle," said Higgins.
But it's not just getting out of the car that's needed, said Dr. Robert Lawrence of the Johns Hopkins School of Public Health. A diet shift away from heavy meat consumption would also go far, he said, because it takes much more energy and land to produce meat than fruits, vegetables and grains.
Recent studies support that argument. Last year the United Nations Food and Agriculture Organization reported that the meat sector of the global economy is responsible for 18 percent of the world's greenhouse gas emissions. Much of that is indirect, including the fertilizer needed to grow massive amounts of feed for livestock, energy use in the whole growing process, methane released from fertilizer and animal manure, and transportation of the cattle and meat products.
Similar calculations were made in a study in September in the medical journal Lancet.
The average American man eats 1.6 times as much meat as the government recommends, Lawrence said. Some studies have shown eating a lot of red meat is linked to a higher risk for colon cancer.
As for fighting obesity and global warming by walking and cycling, don't expect people to do it easily, said Kristie Ebi. She's a Virginia public health consultant and one of the lead authors of the Intergovernmental Panel on Climate Change report.
Citing the decades-long effort to curb smoking, she said, "It turns out changing people's habits is very hard."
___
On the Net:
American Public Health Association: http://www.apha.org/
National Center for Environmental Health: http://www.cdc.gov/nceh/climatechange/