It's OK to pick on fat people in the workplace … isn't it?

Apparently, too many people think the answer is yes, according to a new study from Yale University, which found discrimination against overweight or obese people may not only be the last "acceptable" bastion of prejudice, it may actually be more pervasive than discrimination based on race.

"We found that weight discrimination is very common in American society and it occurs virtually as often as racial discrimination," Rebecca M. Puhl, one of the study's authors, tells DiversityInc. "In fact, among women, weight discrimination was actually more common than racial discrimination."

The study, conducted by Yale University's Rudd Center for Food Policy and Obesity, received input from 1,100 respondents, ages 35 to 74. The subjects answered 11 questions about whether they had been discriminated against in a host of life experiences ranging from employment and medical care to education and interpersonal interactions.

The results? The prevalence of weight discrimination increased from 7 percent in 1995--1996 to 12 percent in 2004--2006, demonstrating a significant increase (66 percent), affecting all population groups but the elderly. While the prevalence of obesity in the United States has remained static for the past few years, it's still high--34 percent of U.S. adults ages 20 and older are clinically obese. Obesity is defined as having a body mass index of 30 or greater.

The Yale study also revealed that women are much more likely to face discrimination because of weight than men. "We found that women are twice as likely as men to be discriminated against, and for men, the risk of weight discrimination really doesn't happen until much higher levels of obesity. For women, it happens at a much earlier bodyweight," Puhl says. "I think women in our culture face very strict ideals of physical attractiveness that are often very unrealistic."

Why is this form of discrimination still tolerated? Puhl believes it's because of perceptions that weight gain is always in a person's individual control. So someone who's overweight or obese is perceived as weak or simply unwilling to take control of their lives. It's a perception Puhl takes strong exception with.

"We have a billion-dollar diet industry based off the idea [of] if you just work hard enough or take this pill, you can get the body that you want. But that's not what the current state of science tells us," says Puhl, who has been studying weight bias since 1999. "Because obesity is perceived to be within a person's control, we perpetuate messages that this is an issue of willpower and personal choice. So it leads to a lot of blame."

That news doesn't come as a surprise to Desda Ravanesi, the Chicago chapter president of the International Size Acceptance Association (ISAA). ISSA works to promote size acceptance and fight size discrimination throughout the country.

"I believe employers may have ideals ... that the average woman may find difficult to obtain for herself," says Ravanesi. "Say they want a receptionist. They want a thin, pretty young girl. But what about a fluffy, pretty young girl? I believe people should be hired for their qualifications. And a fat person does not equate laziness or unintelligence. Nor does it mean someone is inarticulate or not career driven. It just means this happens to be my body type. It does not in any way define who an individual is."

Ravanesi produces a cable television program for and about plus-size women and issues of interest to them. She wants to bring positive messages to her audience with topics ranging from size and self acceptance to programs on health, fitness and plus-size modeling careers.

"Our culture has said you are the wrong body type," she says. "But it's not wrong for us as a plus-sized person. It's perfect for who we are and the place we're in in our lives right now. But now [our society is] on a campaign ... a fat-hating campaign because we want everyone to be very thin."

Adding to the problem is that while laws exists to protect people from discrimination based on  race, gender and age, there are hardly any laws against weight discrimination. No federal laws exist and only the state of Michigan has any legal protections to prohibit weight discrimination, according to the Council on Size and Weight Discrimination. So in most states, if an employer fires you because you're overweight, you would have little legal recourse.

"Weight discrimination is a legitimate social problem. But because there are no federal protections, we're saying this is a form of bias that's tolerated," says Puhl. "If we really want a shift in attitudes, we need legislation that treats this as a serious problem."

Last month, Massachusetts held hearings on a bill which would add weight and height to the state's antidiscrimination law. That bill, sponsored by Rep. Byron Rushing, could open the door for other states to follow suit.

"This is one of the last physical aspects of people that you can acceptably laugh about," Rushing told FOXNews.com. "You can be a shock jock on the radio and talk about fat people for a solid week and no one would ever think of having you lose your job. It's still acceptable."

More Legal Issues >>