25% of Americans are overweight or obese Washington - UPI Obesity is not just a U.S. issue although Americans are still the fattest, a Gallup poll indicates. The Gallup-Healthways Well-Being Index, which tracks obesity in America, Britain and Germany monthly, found Americans are in far worse shape than are Britons and Germans. Twenty-five percent of Americans are obese, compared with 20 percent of Britons and slightly more than 10 percent of Germans, the index indicated. Worldwide obesity has more than doubled since 1980 and being overweight or obese is the fifth-leading risk for global deaths, killing about 2.8 million adults each year with the obese more likely to suffer from chronic conditions, the World Health Organization said. Obese Germans are more than twice as likely as normal weight and underweight Germans to have high blood pressure, high cholesterol and to have suffered a heart attack. Those who are obese are more than six times as likely as those who are normal weight and underweight to have diabetes. The German Gallup Healthways Well-Being Index mirrors the results found in the United States, Gallup said. The Gallup-Healthways Well-Being Index survey, conducted March 7-Sept. 30 of 6,514 adults, has a margin of error of 1.62 percentage points. The British and U.S. Gallup-Healthways Well-Being Index survey was conducted March 1-Sept. 30, querying 6,295 British adults and 200,294 U.S. adults. The British index has a margin of error of 1.45 percentage points and the U.S. index has a margin of error of 1 percentage point.