The average American woman weighs 166.2 pounds, according to the Centers for Disease Control and Prevention. As reddit recently pointed out, that's almost exactly as much as the average American man weighed in the early 1960s.
Men, you're not looking too hot in this scenario either. Over the same time period you gained nearly 30 pounds, from 166.3 in the 60s to 195.5 today. Doing the same comparison as above, today's American man weighs almost as much as 1.5 American women from the 1960s. At 195.5 pounds, put five American guys in a room and you've gathered roughly half a ton of manhood.
Overall weight gain since 1960 is slightly greater for women (18.5 percent) than for men (17.6 percent). And both sexes have gained roughly an inch in height over the same period, which accounts for some of that weight gain.
But story is mostly one of growing girth, and it basically boils down to three factors: we're eating less-healthy food, we're eating more of it, and we're not moving around as much. According to a study published in 2012 in the journal BMC Public Health, Americans are now the world's third-heaviest people, behind only the Pacific island nations of Tonga and Micronesia.
The average American is 33 pounds heavier than the average Frenchman, 40 pounds heavier than the average Japanese citizen, and a whopping 70 pounds heavier than the average citizen of Bangladesh. To add up to one ton of total mass, it takes 20 Bangladeshis but only 12.2 Americans.
Together, the world's adult human beings added up to 287 million tons of biomass in 2005, according to the BMC Public Health study. But if every country had the same weight distribution as the U.S., the world would be 58 million tons fatter, an increase of 20 percent.
The study concludes that "tackling population fatness may be critical to world food security and ecological sustainability." And as with so many of the world's problems, the solutions start at home -- on the bathroom scale in this case. But boy, those doughnuts sure do look delicious.