If you’re overweight, people think you’re a less capable leader. That’s the finding of new research by the Center for Creative Leadership (which I had never heard of until now).

The Wall Street Journal reports that the research found that executives with wider girths and higher BMI (body-mass-index) readings were perceived as “less effective in the workplace, both in performance and interpersonal relationships.”

CCL reportedly arrived at its findings after looking at 757 peer-performance reviews and health-screening results from CEOs and other senior-level types who attend its leadership workshops, collected between 2006 and 2010.

The execs in the study were generally healthier than the average American, says the WSJ, though “about half” were considered obese. If that sounds like a lot, it’s apparently less than the 60% obesity rate of average Americans. They also drank and smoked less, which sort of goes against my image of three martini lunches and overworked, stressed out CEOs quashing their anxieties with Cohibas and single malt.

“The sample’s leaner executives, defined as having a BMI under 25, were viewed more favorably by peers, averaging 3.92 for task performance on a five-point scale; heavier leaders averaged 3.85. Similarly, members of the leaner group rated higher on interpersonal skills.”

So, the difference isn’t that striking. Still, provided this isn’t a coincidence and the girthier subjects just happened to also be jerks, it’s interesting to note that they lost points on “interpersonal skills.”

The WSJ quotes Amanda Sanders, a New York based image consultant as pointing out the obvious: that being overweight can lead others to assume you’re weak or lack self-control. Other behaviours, like smoking and drinking, can suggest the same thing, – but these aren’t necessarily obvious on sight.

Weight bias shouldn’t actually shock anyone at this point.

One story of this sort of discrimination at work comes from a woman named, ummm, Maria who works in film. She tells me, “I worked for a mean production manager who was constantly commenting on what I ate — i.e. “Wow, already in the fridge and it’s only 9:30? — she wouldn’t take me onto the next show because she said she couldn’t afford the food budget.” OK, I think that’s kind of shocking.

Dr. Arya Sharma, Professor of Medicine and Alberta Health Services Chair in Obesity Research and Management at the University of Alberta, is one person who isn’t surprised.

“There has been a lot of empirical research on this,” he tells me, “including studies where you present the same CV to an employer with a picture of an obese person and a non-obese person, and they show a preference for the non-obese person. Interestingly, even obese people themselves will show a weight bias and discrimination against other obese people. This just shows you how ingrained it is.”

It’s true. A lot of people do think obese people are lazy, lack willpower, etc. Is there any truth to it?

Sharma says, “Much of it is rooted in the concept that body weight is controllable, which means that if you really don’t want to be fat there are ways to not be fat. And if you are it’s essentially because you don’t care and lack the motivation and willpower to do it, because it can be done. So it becomes your fault. But, let’s take somebody who breaks their back downhill skiiing. That’s your fault but people will make all kinds of accommodations for you and even think that’s kind of cool, even if you were being stupid.”

He goes on, “Is it really true that obese people are less productive, miss more days at work, lack self-control? There’s actually almost no data to show that. There’s a general assumption that overweight people have more mental health problems and that is not at all true. Assumptions about people’s behaviour just based on weight are not generally born out by data.

“There are lots of skinny people who eat junk food all the time and spend most of their time on the couch watching TV. And lots of large people have regular exercise schedules and are still large. We have to be very careful about making judgements about people based on their size.”

Regardless, all this doesn’t change the fact that your weight might hold you back, fair or unfair.

And it might be easier to change your size than to change people’s minds.