If you feel unhappy, longevity expert and National Geographic Fellow Dan Buettner tells CNBC Make It you should "follow your bliss, not your material desires."
New research published by National Geographic on Wednesday revealed the top American cities where people are "living their best lives," based on a study of 250,000 adults from 2014 to 2015 in 190 metropolitan areas across the country.
Along with a team of Gallup social scientists and Buettner, the publication shared the results of its National Geographic Gallup Special/Blue Zones Index.
The study, published as part of National Geographic's November cover story, also drew upon Buettner's scientific research on happiness, as detailed in his new book, "The Blue Zones of Happiness. "
If you are in search of a happier life, you may want to consider a fresh start in one of the top 10 happiest cities in the U.S., according to the National Geographic Gallup Special/Blue Zones Index.
Boulder, Colorado is the number one happiest city, according to the National Geographic Gallup Special/Blue Zones Index. Thanks to its sense of community, access to nature, sustainable urban development and preservation policies, Boulderites overwhelmingly feel "active and productive every day," National Geographic noted from Buettner's research.
"Per capita, more people walk to work in Boulder than in any other city in the U.S. Low rates of smoking and obesity, and high rates of exercise, contribute to the satisfaction locals feel," according to the publication.
Happiness may arguably seem immeasurable and Buettner admits that academically speaking, it's a meaningless term.
But tied together with statistics, Buettner says you can measure life satisfaction by:
Buettner says that if you want to become happy, you should change your environment, not your belief system.
"Your beliefs aren't going to change. But data now exists to show us how to optimize your surroundings so you're more likely to be happy," he says. "Living by water, in a bikable community and in a place with easy access to fruits and vegetables all stack the deck in favor of happiness."
Gallup senior scientist Dan Witters established 15 measurable expressions of happiness and together with the researchers used them to determine how strongly these resonated with the interviewees.
In his book, Buettner wrote about three "strands" of happiness that were key to formulating the list of happiest cities: pleasure, purpose and pride.
Pleasure is enjoying life in the moment while purpose is about living out your values and passions while serving a greater purpose, he explains. He adds that pride is about how satisfied people feel with their accomplishments in life.
"The formula for solid, long-lasting well-being weaves all three strands of happiness together," Buettner wrote in his book.
Buettner's offers this advice to millennials who may feel unhappy living or working where they do: "As long as you make enough for food, shelter, healthcare and some mobility, you should only do a job you love and uses your skills/passions," he says. "You will be much happier in the long run."
"Also it helps to move to a bikable community and ditch your car," Buettner adds.
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