A happiness expert explains why having a best friend at work is the number one thing you can do to make you more productive and satisfied

Dan Buettner, National Geographic explorer and author of "Blue Zones of Happiness: Lessons from the World's Happiest People," explains four things that will enhance your work life. Following is a transcript of the video.

Dan Buettner: So in my book I outline a number of statistically underpinned things that you can do to make it more likely you're going to like your work life and first and foremost among them is get a job that speaks to your passions as opposed to your bank account. When it comes to income, utility of that flattens out, passion always grows over time.

Secondly, you want to take a job near your home. The thing we most hate in our day-to-day life is our car commute, so minimizing that.

The third thing, and probably the biggest determinant of whether or not you like your job, is if you have a best friend at work, and that comes from two million Gallup surveys. And you start asking yourself, well, how do I get a best friend at work?

Well, it usually involves putting yourself out there, thrusting out your hand to somebody you don't know, inviting them to lunch, doing a happy hour with them. You want to get to the point where your conversation transcends the usual just commercial back-and-forth of work or talking about sports score. You want to find a friend with whom you can have a meaningful conversation and they'll actually care about you on a bad day.

And then the last thing is to think about vacations. You actually get more utility from vacations if you take a lot of small ones rather than a big one, and the ideal number of weeks of vacation per year is six weeks. After six weeks we actually kind of get sick of vacations, but in America we only take about 11 days on average and we could be a lot happier workers if we spread that out closer to the six week ideal.