11/29/2013 10:32 am ET Updated Jan 29, 2014

Why You Need to Slack Off at Work This Week

Every office has an eager beaver. You know the one: arriving before everyone else and still logging hours after the boss has gone home. But during the week of Thanksgiving, even this person is probably taking a day or two off work. This is the magic of the holidays.

And though you may mock and/or resent the eager beaver, you may have more in common with him than you think.

Nowadays, Americans are working more than ever. According to a recent Workforce magazine study, 55 percent of employees have seen their workload increase since the Great Recession, and 27 percent say it's doubled. That means more work and less vacation for almost everyone.

One fairly disturbing poll from Ipsos Public Affairs reveals that 44 percent of Americans have not taken a vacation in more than two years! Assuming they are able to accrue vacation, why would anyone choose not to take the time away that they've rightfully earned?

For many, fear is a factor -- fear of missing out on promotions, topping the layoff list, being judged by bosses or coworkers, or returning to an insurmountable pile of work.

But even though taking time off can feel scary and stressful, it turns out to be far better than the alternative. The research is clear. Working too much makes us stupider, unhappier, unhealthier and less successful. Let's break this down, shall we?

Working too much makes you stupider.
Long hours affect brain functioning. One American Journal of Epidemiology study followed British civil servants over five years, and compared to those who worked 40 per week, participants who worked more than 55 hours showed poorer vocabulary and reasoning skills. In plain English, working too much actually makes us stupider.

Working too much makes you depressed.
Long hours are also a significant risk factor for depression. A study published in Plos One examined more than 2,000 workers in the United Kingdom over six years. They found that employees who worked more than 11 hours per day had more than twice the risk of depression than those who worked eight hours or less. This was true even when researchers statistically removed the influence of chronic physical disease, smoking and alcohol use.

Working too much hurts your career.
When people think about how to get ahead, most have a "more is better" philosophy. Just look at the hours worked at many law firms, tech companies, and Wall Street. But more hours do not always equal better performance -- human beings have an upper limit for productivity on any given day. And somewhat counter intuitively, a 2006 Ernst & Young study cited by Tony Schwartz found a positive relationship between time off and performance: For each additional 10 hours away from the office, employees' reviews were eight percent higher the following year!

Working too much can actually kill you.
In August of this year, a 21-year old Bank of America intern was found dead in his London dorm room. During the course of Moritz Erhardt's demanding seven-week internship, he'd pulled eight all-nighters in two weeks. Although Erhardt's case is as rare as it is tragic, it reflects the general lesson that working too much is simply not healthy. Luckily, when we take time away, these effects are mitigated. The Framingham Heart study, for example, reported that when workers take annual vacations, their risk for heart attack is reduced by 30 percent in men and 50 percent in women.

Two Tips for Taking Time Off Without Paying for It When You Return:
Hopefully, cashing in some of that vacation time feels more important than it did a just few minutes ago (for me, at least, the threat of death tends to have that effect). So, as long as you're not being forced to show up at work at 6 a.m. on Thanksgiving, this is a perfect week to take a few days off to be with your friends and family. Here are two simple tips:

1. It's okay to start small.
Good news: Short vacations have similar positive effects as long ones. One study from Radboud University Nijmegen in the Netherlands found that even vacations of just a few days increased health and well-being. And because benefits from most vacations fade after five days, frequent, shorter vacations may actually be better. So instead of blocking off two weeks and paying for it when you return, go ahead and start with a day or two.

2. Check in with the office if you need to.
If the mere thought of being cut off from work makes you break out in hives, never fear -- it's actually okay to check email a few times while you're away. The above study revealed that people who worked during vacations still showed increases in health and well-being, albeit smaller ones. So, within the bounds of reason, go for it! Just don't let things get out of hand, lest your spouse or partner lock your iPhone in the broom closet.

After a few days away from the office this holiday season, you'll probably feel rejuvenated. Your next challenge is to make this a habit and regularly carve out time away. After all, on his deathbed, even the eager beaver is unlikely to lament, "I wish I had spent more time at the office."