A government campaign has come under fire following the release of a new study that found overweight women earn less than their average-size peers.

LEAN Works!, a program by the Centers for Disease Control and Prevention, offers companies an online tool that lets them calculate the cost of employing overweight people. Employers enter the body mass index of a worker and other data about the company, which the calculator translates into hospitalization and prescription costs and lost workdays. According to the CDC’s website, expenses for obese employees are 42 percent higher than for someone at a healthy weight, and the tool could help employers design wellness programs.

Criticism of the project has mounted after Vanderbilt University released a study that found heavier women earn 5 percent less than average-size women in the same profession. It also reported that overweight women are often forced to take more physically demanding and lower paying jobs.

“Supposedly, LEAN Works! is meant to help companies provide support services for people who are fat. But I think it’s nothing more than a way to identify employees who should be terminated,” Joanne Ikeda, nutritionist emeritus at the University of California, Berkeley, told NBC News. “It really pisses me off that the government has allowed this to happen.”

Then there’s the issue of BMI as a marker of health.

“The fact that this program is based purely on a person’s weight, with no consideration for their health, is a problem,” said Peggy Howell of the National Association to Advance Fat Acceptance.

Jennifer Shinall, the Vanderbilt study’s author, thinks it isn’t about the expense. Her findings suggest that regardless of occupation, obese men do as well as average-size men.

“If medical costs or productivity costs were driving the lower wages and lower employment experienced by obese workers, we would expect to see obese men and obese women encountering similar barriers in the labor market,” she said.

It’s been discussed whether the Americans With Disabilities Act should cover obesity, but Shinall said that because heavier women tend to work strenuous jobs, that might not be the right course of action.

“What seems to be going on in the labor market may be more of a sex discrimination issue,” she said.