How big is the global obesity problem? A new World Health Organization has estimated that the total adult human population weighs in at a whopping 287 million tons -- 3.5 million of which is due to obesity and 15 million to overweight.
The study, published in BioMed Central's open access journal BMC Public Health, is based on an analysis of the world’s population of more than seven billion people. Researchers from the London School of Hygiene and Tropical Medicine came up with the figures using data from the United Nations and the WHO.

Not surprisingly, they found residents of North America have the highest average body mass of any continent. Although they represent only 6 percent of the world's population, North Americans comprise 34 percent of the world's mass due to obesity, they noted. By contrast, Asia has 61 percent of the world's population but only 13 percent of the world's mass due to obesity.
If all countries had the same average weight-per-height as the U.S., the world’s total human weight would increase by 58 million tons - the equivalent of an additional 935 million people of average body mass.