In the United States, obesity among adults increased by half between 1980 and 1994. Surveys in China showed that during the boom years between 1989 and 1992, the share of adults overweight jumped from 9 percent to 15 percent. Juvenile obesity is rising rapidly. In the United States, where at least 1 out of 10 youngsters 6 to 17 years of age is overweight, the incidence of obesity among children has more than doubled over the last 30 years. Not only does juvenile obesity typically translate into adult obesity, but it also causes metabolic changes that make the disease difficult to treat in adulthood.
Obesity is concentrated in cities.
As societies urbanize and people adopt sedentary lifestyles, obesity increases. In both China and Indonesia, the share of people who are obese in cities is double that in the countryside. In the Congo, obesity is six times higher in cities. In a Worldwatch Paper, Underfed and Overfed, Gary Gardner and Brian Halweil report that the number who are overnourished and overweight has climbed to 1.1 billion worldwide, rivaling the number who are undernourished and underweight. Damage to health from obesity takes many forms.