WAISTLINES are widening everywhere. The percentage of adults who are overweight or obese has swelled from 29% in 1980 to 37% in 2013, according to a new study in the Lancet. People in virtually all nations got larger, with the biggest expansions seen in Africa, the Middle East and New Zealand and Australia. The chunkiest nations overall are found in the tiny Pacific islands and Kuwait, where over three-quarters of adults are overweight and over half are obese. And the world is unlikely to slim down soon. While the rate of increase has slowed in the rich world, it is still rising in poorer countries, where two-thirds of the world’s 2.1 billion overweight adults live. China is home to the largest number anywhere—335m, more than the population of America. This is not just because of its sheer size, but also because economic growth led to cellulite growth: a quarter of adults are now overweight compared with one in ten in 1980.Mexicans just outweigh neighbouring Americans. In both countries, two-thirds of people could lose a pound or two, though more Americans are obese. Agreeing on how to combat the problem is tricky, given that experts continue to bicker on what, precisely, makes us fat. Worryingly, the study—led by the Institute of Health Metrics and Evaluation at the University of Washington—showed that children are fattening at a faster pace than adults. Last week the World Health Organisation set up a new commission to curb child obesity. But it will be some time yet before the world reaches peak fat.