It’s 10:00 at night, you’re getting ready for bed (because you’re trying really hard to get those 8 hours of sleep you know you need for peak productivity), and your phone buzzes. It’s a new email from your co-worker. Without a second thought, you open up your inbox to check it and get sucked right back into the office.

We’ve all been there. In an age of high-speed Internet and mobile devices, making ourselves available 24/7 has become a habit. Whether it’s that project we want to keep moving, an urgent question our boss needs answered, or the desire to set ourselves apart for that promotion on the horizon, we feel the pressure to stayed plugged in well beyond the 40-hour work week. Going a weekend without checking email? No way. Taking a whole two consecutive weeks off for vacation? Forget it.

Vacation policies and trends around the world

Legally guaranteed vacation time is very much the norm among developed countries– the United States being the one notable exception. Austria, Germany, New Zealand, the United Kingdom, Sweden, Norway, and Japan all mandate a minimum of 30 or more paid days off (including national holidays) annually. In many of these countries, it’s common to take a full month or more off during the summer.

Several French and German corporations have even instituted no-after-hours-email policies. For the past three years, Volkswagon has programmed its email server to only deliver new messages during work hours to force its employees to disconnect while off the clock.

Compare that to the US where employers are not legally required to grant any paid days off. A survey published by Glassdoor.com found that, on average, American employees who do receive paid time off from their employer only use half of their allowed vacation time, with a full 61% reporting that they work on the vacations they do take. And it’s only getting worse. A survey conducted by Oxford Economics and funded by the U.S. Travel Association found that the typical family vacation in 1975 was a week long. In 2010, it had dropped to just 3.8 days.

Yet a handful of extremely successful companies are bucking this trend. Following Netflix’s lead, Richard Branson announced this year a “non-policy” of paid time off at Virgin Group; in other words, “take as much as you want.” Groupon, Evernote, Zynga, SurveyMonkey, and EventBrite similarly offer unlimited vacation time.

So what’s the catch? Did Richard Branson suddenly wake up and decide that employee happiness is more important than profits? Of course not. He listened to the mounting research and made the strategic calculation that employee happiness is profits. Let’s take a look at how working less can actually make you, and by extension your company, more healthy and productive.

Time away from work makes for healthier, more productive employees.

The idea that working fewer hours actually increases productivity is not a new one. Henry Ford himself voluntarily instituted a 40-hour work week in his auto plants (the norm at the time was 12 hour days, seven days a week) based on internal research that showed a significant increase in worker errors beyond a 40-hour limit. Similarly, a study of British factory workers during World War II found that beyond 49 hours a week, increased hours led to smaller and smaller gains in output. In fact, output at 70 hours per week was only slightly higher than output at 56 hours. That’s a whole 14 hours almost completely wasted!

Though today’s modern knowledge economy requires an entirely different skill set than the heavy industry of the early 20th century, more recent studies show that the same principles of worker productivity still apply. A 2011 International Labor Organization study of OECD countries from 1950 to the present found that, as number of hours of work increased, productivity per hour decreased. Furthermore, the report found that the more hours worked, the faster productivity plummeted, just like in the British munitions factory. The graph below put together by The Economist shows the stark negative correlation between hours worked and productivity per hour.

Why the dramatic loss in productivity? In one word: Stress. Almost three-quarters of Americans say that they are stressed, with one in four stating that they are either “very” or “extremely” stressed. In The Biology of Business Performance, a report sponsored by Wellness & Prevention, Inc. a Johnson & Johnson company, found that stress created by the nearly constant demands of the modern workplace leads to disengagement from work, anxiety, depression, and sleep deprivation. Workers who are unable to manage their stress at work are more likely to be impatient, uncooperative, defensive, hyper critical and pessimistic, hampering personal and team productivity.

The cumulative effects of long-term, unrelenting stress are all too often burnout, low performance, and lack of innovation– not to mention poor physical and emotional health. One long-term study found that male participants who had skipped vacation for five or more consecutive years were 32 percent more likely to have heart attacks than those who took at least one week off a year. Even more astonishing is a study that found that women who hadn’t taken a vacation in six or more years were eight times more likely to develop heart disease than women who vacationed at least twice a year!

There’s an easy solution: Take more vacation! In the Oxford Economics/US Travel Association survey, 90% of respondents said that PTO helps them relax and recharge, 85% said it makes them happier, 65% said it improves their concentration and productivity, and 61% said it contributes to greater work satisfaction. A study of 1,500 women from rural Wisconsin showed that participants who took at least two vacations a year were less likely to be tense, depressed, or tired than those who only took vacations every two years. The bottom line is that taking a break allows you to come back re-energized, re-focused, and more ultimately resilient in the face of work’s inevitable stresses.

How to use your to-do list for a guilt-free, unplugged holiday:

It’s one thing to read all of the anecdotal evidence and science-backed facts about the benefits of a work-life balance. It’s another thing entirely to actually unlearn our deeply ingrained, workaholic habits and give ourselves permission to take a real break.

If you’re reading this post, it’s likely that you’re highly motivated by your to-do list. This holiday season, do your long-term health and productivity a favor by using Todoist (or whatever task management system you use) to set yourself up for a guilt-free, no-work-allowed vacation.

Set aside some time this week to reset your to-do list so you can head into the holidays feeling in control with a clean slate:

Set a realistic schedule for what you need to get done before the holidays to be able to unplug guilt-free. Realistic is the operative word here. Be honest with yourself. Laura Vanderkam, author of 168 Hours: You Have More Time Than You Think , recommends asking yourself “What am I going to feel the greatest relief having gotten done?”. Focus on your absolutely have-to-do’s and the big wins on your task list.

Realistic is the operative word here. Be honest with yourself. Laura Vanderkam, author of , recommends asking yourself “What am I going to feel the greatest relief having gotten done?”. Focus on your absolutely have-to-do’s and the big wins on your task list. Delegate or delete old tasks you know you’ll never get to or you’ve decided just aren’t worth it. We’ve all got those nagging tasks that keep getting pushed to the bottom of the list. The upcoming vacation provides the perfect opportunity to get them off your to-do list and your mind once and for all.

We’ve all got those nagging tasks that keep getting pushed to the bottom of the list. The upcoming vacation provides the perfect opportunity to get them off your to-do list and your mind once and for all. Reschedule everything else for after your vacation. Knowing you have a solid plan for taking care of things when you get back to the office will allow you to relax and enjoy your break. And trust me, waking up to this page on Christmas morning will be priceless:

If you’re one of those people who is addicted to seeing your Todoist Karma points go up daily, try setting a task for going to that movie you’ve been wanting to see, curling up with some hot chocolate and a good book, spending quality time with family, or NOT checking your email for a change.

Most importantly, turn off the email notifications, and remind yourself that taking time off is not a sign of weakness or lack of commitment, it’s an investment in your health, happiness, and productivity. Relax and enjoy!