As nearly two thirds of Americans wolf down their mid-day meal at their desks, chances are you probably don't get out of the office for lunch on a regular basis.

It's not hard to understand why. A quick sandwich while you catch up on emails or the news seems like an easy way to get your work done faster and home to your family and friends that much quicker.

But it turns out your in-office lunches aren't just uninspiring on a culinary level, but also a false economy when it comes to saving time. Eating at your desk may make you less productive rather than more overall.

How? Recently, author Bob Pozen shared some lunchtime wisdom. There are often better ways of putting your sandwich-scarfing time to use:

The desk-lunch efficiency might not be worth it, he says, if you could gain more from stepping away.

You could eat alone--perhaps away from a screen. Pozen says that since you’ll sometimes have a very full day, eating alone can help you restore your personal resources. And don’t pull out your phone: An absence of stimulation encourages associative or integrative thought, spurring your creativity. As well, if you have an idea that you’re working on in your head, eating alone allows you to continue uninterrupted.

Another option is to address the afternoon energy crash: You could take a walk or hit the gym, or, alternatively, you could take a 20-minute nap. What works is individual, Pozen says, so it might be a good idea to experiment with a few different approaches.

Taking a break and stepping away from your screen, in other words, may cost you a bit of time now, but it'll save you more in the long run thanks to the productivity boost you'll get from refreshing your brain and your body.

This argument against eating at your desk comes on top of several other reasons to take a real break. Lunch is a great networking and relationship-building opportunity and eating with negotiating partners has been shown to improve the profitability of the eventual deal. Mindlessly shoving whatever is convenient in your mouth isn't awesome for your health or your waistline (or your enjoyment of life). Plus, your desk is filthy. So maybe it's time to bring back a proper lunch break.

Do you eat lunch at your desk?