A new study finds one third of the world's population is overweight or considered obese.

　　Since 1980, obesity rates in children and adults have doubled in 73 countries. And rates are increasing in many other countries, according to a report released on Monday.

　　The report was published in the New England Journal of Medicine.

　　Obesity is increasing faster in children than adults in many nations, including Algeria, Turkey and Jordan, the report said. But the world's weight problem is growing in both rich and poor countries alike.

　　Researchers say an increasing number of people are dying of related health problems in what they called a "disturbing global public health crisis."

　　About four million people died of cardiovascular disease, diabetes, cancer and other diseases linked to excess weight in 2015, according to the study.

　　"People who shrug off weight gain do so at their own risk," said Christopher Murray, one of the writers of the report.

　　Researchers studied health information from 1980 through 2015. They examined obesity rates, average weight gain and the cause of death in 195 countries. They found that obesity rates are three times greater among youth and young adults in countries like China, Brazil and India.

　　Almost 108 million children and more than 600 million adults were found to be obese. Together, that represents about 10 percent of the world's population.

　　Among the top 20 most populous countries in 2015, Egypt had the highest number of age-standardized obese adults. Vietnam had the least. In the same year, the United States had the highest number of obese children, and Bangladesh had the least.

　　Researchers say the extra weight people are carrying increases their risk of developing diabetes or other health problems.

　　Yet hunger remains a problem in many areas. The United Nations estimates that almost 800 million people, including 300 million children, go to bed hungry each night.

　　Experts said poor diets and lack of physical activity are mainly to blame for the rising numbers of overweight people.

　　Growing populations have led to rising obesity rates in poor countries. Often, poor people will eat processed foods instead of choosing a diet rich in vegetables.

　　"People are consuming more and more processed foods that are high in sugar and fat and exercising less," said Boitshepo Giyose, senior nutrition officer at the U.N. Food and Agriculture Organization.

　　The London-based Overseas Development Institute studied the price of food in five countries: Britain, Brazil, China, Mexico and South Korea. It found that the cost of processed foods like ice cream and hamburgers has fallen since 1990. But the cost of fresh fruits and vegetables has gone up.

　　I'm Anne Ball.

　　Anne Ball wrote this story for Learning English, with information from the Thomson Reuters Foundation and the Associated Press. George Grow was the editor.

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