That’s why, in recent years, as the American population has become generally more overweight, brands from the luxury names to the mass retail chains have scaled down the size labels on their clothing.

“You may actually be a size 14 and, according to whatever particular store you’re in, you come out a size 10,” said Natalie Nixon, associate professor of fashion industry management at Philadelphia University. “It’s definitely to make the consumer feel good.”

Research shows that, when it comes to self-perception, the concept of “overweight” may be relative.

A working paper from a group led by Mary Burke, senior economist at the Federal Reserve Bank of Boston, Massachusetts, suggested that people’s perceptions of overweight have shifted, and “normal” is now heavier than it used to be.

Researchers used data from the National Health and Nutrition Examination Surveys, nationally representative surveys run by the Centers for Disease Control and Prevention. The first group was surveyed in 1988-1994, and the second was surveyed in 1999-2004. Because there were different people in each survey, it is not possible to tell if the perceptions of individuals shifted over time, the authors said.