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Real friendship is the key to our long-term career success, health and happiness. Our basic human need for friendship gives us the sense of belonging, purpose, confidence and satisfaction that we crave. Yet we often overlook our fellow co-workers as friends because we try to separate our needs in the office from those at home. The problem with that mentality is that our core needs remain the same regardless of our environment — after shelter and food, we need deep human relationships. As the average workweek continues to expand, between the demands of the new economy and our always-on culture, we can no longer be fulfilled without befriending our colleagues. Today's workforce suffer from a lack of work friends, and it's become a global epidemic. HR advisory and research firm Future Workplace recently conducted a study with Virgin Pulse of more than 2,000 managers and employees in 10 countries. The study revealed that nearly 1 in 10 people have no friends at work, and more than half have five or fewer. Those with few friends said they felt lonely either very often or always and disengaged in their work. Almost two-thirds said they would be more inclined to stay at their company longer if they had more friends. This is especially true for millennials, who consider their manager as their work parent and their co-workers their work family. A separate study, by Officevibe, found that 70 percent of employees say friends at work is the most crucial element to a happy working life, and 58 percent of men would refuse a higher-paying job if it meant not getting along with co-workers.

Strong bonds mean positive performance

Work friendships make us feel safe, but they also help us perform at a higher level. Donald Clifton, the former educational psychologist who founded Gallup, found that these relationships are one of the strongest predictors of productivity. Gallup research has found that those who have strong work relationships are more engaged, produce higher-quality work and have a higher state of well being. Jennifer Schopfer, vice president and general manager of Transport Logistics at GE Transportation, was tasked with driving a new strategy and process across both her organization and another one within GE. Knowing it would be challenging, she made a call to one of her close friends, who played a critical finance role in that organization. "She helped me to better understand the people and the business model of that organization so that we could adjust the value proposition of the proposed changes to better incent them to participate, while still ensuring a financial model that worked for all," Schopfer explained. Workers today spend a third of their lives at work. The Future Workplace/Virgin study found that 71 percent of employees say work interferes with their personal lives. Our research shows that half of managers expect employees to respond to emails and phone calls outside of the office. And we all are guilty of responding to work emails on vacation! Our work friendships impact our mood, happiness and overall fulfillment. The absence of friendship leads to dissatisfaction, depression and eventually turnover. The division between work and life becomes blurrier by the day. In a conversation I had with Sir Richard Branson, founder and chairman of the Virgin Group, he said, "If at home, you've got friends, you should have an equal number of friends in the workplace." He went on to say, "You should never feel that you are chained to a desk at work. An employer is only going to get proper rewards from an employee if they love what they're doing. We need a lot more flexibility in the workplace than a lot of companies give today."

Hard times are inevitable in our unpredictable world, where mergers, acquisitions, layoffs and mobility are the norm. The friendships we have enable us to handle these changes.

Today's leaders know we can no longer separate one from the other, because the work we do is such a big part of our identity. "The reality is that work is such a big part of your life that it doesn't make sense to think of "work" and "life" as two separate things that must be balanced. Your life doesn't stop when you enter the office, just like your work may not stop when you enter your home," says Mathew Mehrotra, head of the Canadian personal banking digital experience at BMO. We need friends to satisfy our needs for companionship, love and safety. We seek their comfort and their help in dealing with the stress, politics and hostility that exists in the workplace. We need them to turn to when issues arise around sexual harassment, bullying, layoffs and poor management. A study of more than 3,000 workers by Rand found that 1 out of every 5 say they face a hostile or threatening work environment. Paul Reich, senior vice president of local sales at Yelp, told me, "When we feel personally connected to our peers, we're more likely to persevere through difficult times at work rather than leave the company." These hard times are inevitable in our unpredictable world, where mergers, acquisitions, layoffs and mobility are the norm. The friendships we have enable us to handle these changes. Rashida Hodge, director of Worldwide Client Delivery at IBM, experienced the power of friendship firsthand, which ultimately led her to stay with the company through hard times. "When I moved on assignment from Raleigh to New York City, I was strapped for cash, given the significant cost-of-living change. It was one of my managers that took me in as a "daughter" and introduced me and made me a part of his family." Aside from her manager's act of kindness, it was the daily talks, drinks after work and pep talks that provided her comfort and made her stay with IBM, despite other choices.

A happy environment can improve health

Researchers at Tel Aviv University studied the impact of co-workers on one's health. They tracked 820 adults over the course of 20 years, examining the various conditions around their job, while asking questions about their co-worker relationships, their boss' behavior and work environment. They monitored their health during that time period and found that the environment had almost no impact to their health, nor how poorly their boss treated them. Instead, they discovered that the support of their co-workers was most closely linked to good health and that less-kind teammates were associated with a higher risk of dying. They concluded that middle-age workers with little or no "peer social support" in the workplace were 2.4 times more likely to die during the study.