The Yale Rudd Center for Food Policy & Obesity maintains a media gallery to fight obesity stigma.
The Yale Rudd Center for Food Policy & Obesity maintains a media gallery to fight obesity stigma.

Why Do Obese Women Earn Less Than Thin Women (and Obese Men)?

For more than two decades, economists have noticed that obesity has a, well, weighty impact on income, particularly for women. A well-known 2004 study, for example, found that a 65-pound increase in a woman’s weight is associated with a 9-percent drop in wages — an obesity penalty equivalent to about three years of work experience.

“But economists have been really puzzled as to why,” says Jennifer Bennett Shinall, an assistant professor of law at Vanderbilt University. “Why are female obese individuals doing worse in the labor market?”

Research has focused on three possible explanations. The first points the finger at the employee herself. It says that obese women are choosing to work in jobs that happen to pay less.

The other two explanations focus on the employer. One says that employers are paying obese women less because they’re less productive. “It’s the idea that weight gets in the way of you doing your job,” Shinall says.

The final explanation suggests that employers are paying obese women less because of personal preferences: either they don’t like working with obese women, or they’re concerned that their customers or clients would prefer not to work with them.

Earlier this year, Shinall published a study that attempts to pick apart these three hypotheses. Her research pulls from a wide array of datasets detailing, among other things, employee body-mass index, wages, and the job industry. But most important is the data Shinall used to categorize various occupations. She analyzed them based on two measures: how much they depend on physical activity, and how much on personal interactions. Being a nurse or cook, for example, involves more physical activity than having an office job. And a salesperson relies on personal communication more than, say, a computer programmer. Jobs with high levels of physical activity tend to pay less than jobs with high levels of personal interactions.

Shinall’s analysis found, somewhat counter-intuitively, that obese women are more likely to work in physical jobs than other jobs. In fact, the heavier a woman is, the more likely it is that she’ll work in a physical job. (Obese men are also more likely to have physical jobs, but that’s not true for morbidly obese men.)

What’s more, morbidly obese women who do work in jobs with lots of personal interactions make 5 percent less than normal-weight women in the same jobs, the study found. And both of these findings persist even after controlling for race, age, education, presence of a child, and geographic region.

These results, according to Shinall, don’t fit well with two of the three hypotheses. Consider the one that says the wage gap is the result of an obese woman’s personal choice. Given that obesity sometimes* affects basic physical abilities (such as walking more than a quarter of a mile, going up a few stairs, stooping, or lifting objects), why would obese people choose more physically demanding jobs? And even if, for some reason, they found personal-interaction jobs more unpleasant, then basic supply-and-demand theory would suggest that obese women in those jobs would demand more money, not less.

Then there’s the hypothesis about obese women earning less because they’re less productive. That’s not convincing, Shinall says, because obesity is most likely to affect productivity in physically demanding jobs. If employers were really concerned about this, wouldn’t they be less likely to hire obese people for physical jobs?

Plus, if it were all about obesity-related disability, then why would there be differences between obese men and obese women? “Just the fact that we see very different results for women than we see for men is suggestive that this is some sort of sex-based discrimination issue,” Shinall says.

Discrimination. That’s a scary, loaded word, and Shinall readily admits that this data does not prove that obese women are being discriminated against. But her paper outlines similar findings from a variety of disciplines, and I think it sounds awfully plausible.

A number of studies, for example, have shown that obese people tend to be rated significantly less attractive than thinner people. And attractiveness, unfortunately, has a lot of influence in the workplace. One study found that attractive people are more likely to work in personal-interaction jobs, such as being a sales person, receptionist, cashier, or waiter. Another study looked at lawyers and found that attractive ones tend to work in the private sector — where they have to drum up their own business — whereas less attractive attorneys work in the public sector. Attractive lawyers are also more likely to be litigators.

A few years ago, Swedish researcher Dan-Olof Rooth sent a bunch of fake applications to real job openings. The applications included facial photos, and he used pairs of photos of the same person digitally manipulated to look more or less obese. Rooth found that applications with the obese version of the photo were less likely to get called back for interviews than the same applications with the thin version of the photo. The call-back response was six percentage points lower for photos of obese men and eight percentage points lower for obese women.

OK, so there seems to be obesity-based discrimination. But why, I asked Shinall, would this be stronger for women than men?

She answered with a telling anecdote about what happened once while she was presenting her data at an academic meeting. “Somebody’s comment was, ‘Well, this makes sense because fat guys are fun.’ Which is sad, but it rang very true with me,” she said. “There is this perception in society that it’s a little bit more OK to be obese if you’re a man.”

Some research supports that idea. A 2011 study surveyed adolescent boys and girls on their attitudes about obesity. The kids indicated that they’d “rather be a fat guy than a fat girl,” and that “it’s more normal for guys to be overweight.”

If Shinall’s analysis is correct, then obese women are facing a major injustice in the workplace. What, if anything, can be done about it?

Shinall, a lawyer, has thought a lot about this. In the U.S., she told me, one state (Michigan) and nine cities have laws prohibiting workplace discrimination based on weight. For all other jurisdictions, obese women might be able to sue their employers based on sex discrimination.

That’s because of something called a “sex-plus” claim to Title VII of the Civil Rights Act, the law that made it illegal to discriminate on the basis of race, color, religion, sex or national origin. Sex-plus claims are for employers that aren’t discriminating against all women, but against women with a particular attribute, such as marital status or age. The first big sex-plus case was in 1971, when the Supreme Court decided that the Martin Marietta Corporation (now Lockheed Martin), could not refuse job applications from women with young kids while hiring men with young kids.

It would be crazy today, but at the time The Martin Marietta Corporation had an explicit policy against hiring women with young children, claiming that they were unreliable employees. Using the same legal precedent for obesity cases would be trickier, but that’s where Shinall believes her study could have a big impact. “What my research is getting at is that employers are treating heavier women differently not as part of an explicit policy, but an implicit policy,” she says. The sex-plus approach “is a potential remedy, but one that hasn’t really been tried yet.”

*I say “sometimes” because the link between obesity and health is complicated. There are lots of obese people who are fit, and lots of skinny people who are unhealthy. In aggregate, though, obesity (and particularly morbid obesity) is a risk factor for physical disability.