I know for me, it's a pretty common thing to have my lunch at my desk. I always figured it was a great idea. I get some work done and polish off lunch too! But is that really the best use of my time?

Longer workdays combined with job security have helped make the desk lunch a threat to disappear.

In 1990, a Gallup Poll found that more than half of Americans took at least 30 minutes for lunch, but now, only a third leave their desks to do so. Even executives seem to have ditched the time-honored tradition of brokering deals over a “power lunch” — a 2011 survey conducted by CareerBuilder found they’re now are twice as likely to bring lunch from home instead of going out.

According to Kimberly Elsbach, a management professor at UC-Davis who studies workplace psychology it is not really resulting in higher productivity.

“Never taking a break from very careful thought work actually reduces your ability to be creative,” she says. “If you’re skipping lunch to continue to push forward in a very intense cognitive capacity, then you’re probably not doing yourself any favors.”