How many times have you asked an employee about his or her stress level only to get the response that they are too busy to be stressed? Whether overworked, overstressed, or a combination of the two, employees keep putting off taking a day off to relax and recharge.

Taking a vacation means to vacate, leave, or go away. However, just because an employer offers vacation days and paid time off doesn’t mean that employees are going to take them. And it appears that many employees are staying at work and not taking their available time off.

An article on Workforce.com said that 2,000 adult employees in the U.S., who responded to a survey by Glassdoor, revealed that they used only half of their eligible time off in the past year. Another 15% of the survey participants hadn’t taken any vacation days in the past 12 months. Why? An expert at Glassdoor said it was fear of losing their job that kept employees from taking time off.

That same survey found that of the employees who did leave the office, more than 60% tended to continue working during their time off and almost 25% of the participants said they were contacted by coworkers concerning a work-related matter — 30% were contacted directly by their boss. That means employees don’t believe they are “allowed” to disconnect from the office.

A different, but similar article on CNN.com stated that employees convince themselves that feeling overwhelmed, stressed out, and not having time to take a day off is normal. But it’s not normal. Plus, by not taking time off, the stress can become too much to handle and may cause employees simply to call in sick and lie to the boss. This creates its own level of stress for the employee.

An employee who feels the need to take time off, but doesn’t, should be told that a way to maximize time off with a minimal impact to work would be to take a few days at a time instead of an entire week — perhaps around a holiday to turn one day off into a three or four day weekend.

According to the CNN.com story, employees can develop a “learned helplessness” that’s self-defeating and dangerous because it can lead to an undervaluing of self-worth. While stress can initially improve performance, over time or if the stress is excessive, then performance is reduced and employees don’t do things as well as they should. Obviously, chronic stress is bad for anyone’s mental and physical health and stress can often sneak up on a person when they least expect it, thus compounding the problem. Reducing stress allows an employee to be more productive, think more clearly, and work at a higher level.

Supervisors and HR departments can reduce this problem by insisting that employees take time off and REALLY take time off. Employees should be encouraged to unplug completely from the duties and responsibilities of work such as not answering their phones, stop checking email, and making themselves totally unavailable. Supervisors can lead by example and set the standard for the rest of the office.