In Hebrew, there's a concept called "distance" that refers to keeping a distance between a subordinate and the person in charge. So, for example, a lieutenant in the army treats his soldiers with "distance," refraining from getting too friendly with them.

That concept often carries over into the business world, with bosses assuming that they need to keep a sense of distance from their employees in order to maintain a hierarchy at the company that fosters respect and hard work. You don't want your employees to forget who's in charge and you don't want to seem too soft.

But as Stanford University's Emma Seppälä points out in Harvard Business Review, this probably isn't the best way to approach leadership. For one, being a tough, distant leader often adds stress to your employees, which is proven to harm your employees' health and increase the likelihood of them quitting. A report from BMC Public Health shows that health care expenditures were 46 percent greater for employees with high levels of stress. Another study shows how occupational stress leads to employee turnover.

On the other hand, research shows that being a nice boss can be incredibly beneficial for both employees and a business. A study from the University of Kent at Canterbury finds that being altruistic can actually increase your status in a group. Other research from Harvard Business School's Amy Cuddy explains that leaders who project warmth earn their employees' trust and as a result are more effective than tough leaders. Then there's another study that shows that a leader's good attitude can spread to his or her team and cause them to be more civil and productive.

Seppälä points to additional studies that show other benefits of being a kind leader: Employees will feel more loyal and committed, will be more likely to help their co-workers, will treat customers better, will be less stressed overall, and will even have better health.

"A good boss may literally be good for the heart," writes Seppälä, the associate director of Stanford's Center for Compassion and Altruism Research and Education.

Now that the importance of being a nice boss has been established, it's important to recognize what that actually means. It might translate into offering perks to your employees, like being able to work from home or extra vacation time. But it also means that you simply have to treat employees with respect and kindness and show a true commitment to values, ethics, and self-sacrifice.

"Creating a leadership model of trust and mutual cooperation may help create a culture that is happier, in which employees help each other, and (as a consequence) become more productive in the long run," Seppälä writes. "No wonder their nice bosses get promoted."