Flickr / Julian Haler.

Have you taken any vacation time so far this year? Are you planning to? If you are like many American workers these days, the answer is, "No". For various reasons, employees are using just about half of their allotted vacation days, even though this often means that they forfeit the time.

Workers have put their work ethic in overdrive since the Great Recession, swapping time off for a chance to look better in the eyes of the boss. New evidence, however, suggests that rested employees actually get more done – and enjoy better overall health – than their nose-to-the-grindstone counterparts.

Job insecurity could lead to illness
Despite mounting evidence that taking time off is good for workers, 30% of employees don't dare take vacation time for fear of falling behind at work, according to a survey earlier this year by staffing firm Robert Half.

A new study by the U.S. Travel Association calls this problem the "Work Martyr Complex", in which employees work more and play less due to fear that they may be replaced. Over one-third of respondents said that they don't take time off because no one else has the ability to do their job.

Research shows that time off can be healthy. The ongoing Framingham Heart Study has linked vacations with cardiovascular health, with even one vacation-free work year resulting in additional heart stress. Vacations don't have to be long, or exotic – taking a few days doing whatever is enjoyable will help keep the circulatory system in good shape, and, possibly, add years to employees' lifespans.

Employers to workers: take a break
Some employers know the value of restored and renewed employees. Back in 2006, auditing firm EY, formerly known as Ernst & Young, found that for every 10 hours of vacation taken, employees scored 8% higher on performance reviews.

Framingham, Massachusetts software company AndPlus now allows employees to bank their unused vacation days, and plans projects so that team members can make use of down time to take time off throughout the year. Marketing software company HubSpot in Cambridge has unlimited vacation for its employees, eschewing the entire bureaucracy usually dedicated to parsing out time off. Instead, employees meld their leisure and work schedules more seamlessly, and the company has more time to dedicate to its customers. 

As more companies realize the value of work-life balance, encouraging employees to take time off may become a lot more common. As Robert Half notes, overwork causes burnout, leading to a loss of creativity. Managers should not only urge their workers to take a vacation, but should practice what they preach, by taking time off, too. After all, no one wants a stressed-out boss, right?

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