Almost one-third of the world’s population is overweight or obese, according to results of a new survey based on data from 180 countries. The research, published in the prestigious medical journal The Lancet, was carried out by the Institute for Health Metrics and Evaluation at the University of Washington. It looked at the prevalence of excess weight and obesity among children and adults, spanning a period between 1980 and 2013. The results show a striking rise in people’s weight over the last three decades.
In numbers: 857 million people were overweight in 1980 as compared to 2.1 billion in 2013, a much higher proportion of the world’s population.
The researchers based their study on the commonly used Body Mass Index, an accepted measure of the relationship between a person’s height and weight. According to the World Health Organization, a BMI value lying between 25 and 29.9 indicates overweight, while values of 30 and above indicate obesity.
The researchers noted that the increased incidence of obesity is common to both advanced and developing nations, and that more than half of all overweight people are concentrated in only 10 countries, including the United States, Germany, China and India. Most of the 671 million obese people are concentrated in the U.S.
They also found that the largest relative increase in weight in the past three decades occurred in the Middle East, in countries such as Egypt, Oman and Saudi Arabia.
What concerned the researchers most was the rapid rise in child and youth obesity. They point to the serious medical implications for childhood obesity, including development of cardiac and blood vessel disease, diabetes and many types of cancer.
“Because of the established health risks and substantial increases in prevalence, obesity has become a major global health challenge,” they wrote. “Not only is obesity increasing, but no national success stories have been reported in the past 33 years. Urgent global action and leadership is needed to help countries to more effectively intervene.”
In accompanying interpretation of the research, written by Prof. Klim McPherson from Oxford University, he praised the researchers although he also added that some of the basic data was “somewhat fuzzy” due to the statistical methods employed.
“Politicians can no longer hide behind ignorance or confusion,” said McPherson, calling on them to devote more resources to combat obesity. Along with bad nutrition and lack of exercise, McPherson noted other contributing factors to obesity such as medications, stress, lack of sleep and a genetic disposition.
These updated figures concord with the gloomy picture presented in recent years by the WHO, which sees obesity as a real risk factor. According to the WHO, 1.4 billion people over the age of 20 were overweight in 2008, 500 million of them obese. Of these, 300 million were women and 200 million were men. Each year, 2.8 million people die from overweight or obesity-related causes. These numbers do not include mortality from diabetes, cardiac disease or cancer, some of which is attributed to excess weight.
According to WHO figures for 2012, more than 40 million children under the age of 5 across the globe suffer from obesity. More than 65 percent of the world’s population live in countries in which mortality from excess weight or obesity is higher than mortality from malnutrition. In May 2013, the UN and the WHO issued a call to stop the global obesity epidemic using, among other means, high taxation on calorie-rich foods and a ban on junk food advertising directed at children.