Mankind weighs millions of pounds more than it should, according to a new study.

Researchers told the International Science Times the extra weight is equivalent of having an additional 242 million people on the planet.

Using World Health Organization data from 2005, the researchers from the London School of Hygiene and Tropical Medicine estimate that North Americans weigh 41 pounds more on average than the average global body weight of 137 pounds.

The researchers fear fat people’s need to eat more calories to survive will become an issue of “environmental sustainability,” and a diminishing food supply.

“When people think about environmental sustainability, they immediately focus on population,” Professor Ian Roberts, one of the researchers, told the BBC. “Increasing population fatness could have the same implications for world food energy demands as an extra half a billion people living on the earth,” said the report.

Obesity is generally associated with wealthy nations, but that doesn’t have to be the case. Roberts points to Japan as an example of where “you can be lean without being really poor.”