The world isn't getting smaller, it's getting fatter, according to a comprehensive report published Thursday in The Lancet.
Whether you're looking at men or women, children or adults, citizens of rich countries or poor ones, people were much more likely to be overweight or obese in 2013 than they were in 1980, the study found.
In developed countries, 16.9% of boys and 16.2% of girls were overweight or obese in 1980. By 2013, those figures were 23.8% and 22.6% respectively. Even in developing countries, the prevalence of overweight and obesity among boys rose from 8.1% to 12.9% and the prevalence among girls grew from 8.4% to 13.4%, the researchers found.
All over the world, the passage of time was marked by bigger waistlines. "Successive cohorts seemed to be gaining weight at all ages, including childhood and adolescence," the researchers found. The most rapid period of weight gain came between the ages of 20 and 40.
A few extra pounds may seem harmless, but their cumulative effect is serious, public health experts say. The Centers for Disease Control and Prevention warns that being overweight or obese will increase your risk of such life-threatening conditions as coronary heart disease, Type 2 diabetes, stroke and certain types of cancer, among other problems. A 2010 study in The Lancet estimated that overweight and obesity caused 3.4 million deaths worldwide.
Tonga had the dubious distinction of having a majority of the adult population considered obese. In addition, six other countries had obesity rates above 50% for women: Kuwait, Kiribati, the Federated States of Micronesia, Libya, Qatar and Samoa.
The United States earned special mention for its "high prevalence of obesity" – 31.6% of men and 33.9% of women. The researchers noted that 13% of the world's 671 million obese individuals live in the U.S. – more than any other country.
Indeed, more than half of the world's obese people lived in just 10 countries in 2013: The U.S., China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan and Indonesia. China and India actually had "low" rates of obesity – only 3.8% of Chinese men and 5% of Chinese women were obese in 2013, along with only 3.7% of Indian men and 4.2% of Indian women. But both countries are so populous that they still came in at No. 2 and No. 3 on the worldwide list.
Perhaps this was the most depressing finding in the entire 16-page report: "No countries had significant decreases in obesity in the past 33 years."
"Public health efforts are leading to progress in tobacco control and cardioprotective diets in a slow and deliberate way. As a result, deaths caused by smoking-related diseases and cardiovascular diseases are decreasing," wrote McPherson, a visiting professor at the University of Oxford. "Can a similar success with weight ever happen?"
Probably not any time soon, he conceded. For policymakers, tackling obesity is like tackling climate change: Experts have a good idea of what needs to be done, but there is simply no political will to make such radical changes.