When was the last time you felt a light-hearted awareness where you had a skip in your step, care-free grin on your face, and overwhelming sense that despite what happened, everything was going to work out? In other words, when was the last time you were truly happy?

It's an amazing, but often fleeting, feeling. And many of us don't get enough of it. What's more, there's a common belief that if we seek out things like a better career, more money, and meaningful companionship, we'll be happier as a result. But that may be a harmful misconception. Science journalist Wendy Zukerman explained the idea on a recent episode of the podcast series Science VS.

To measure the level of happiness in people around the world, scientists use large surveys like the Mappiness app and the World Happiness Report where thousands of volunteers answer questions about how satisfied they are with their quality of life, overall wellbeing, and happiness. While the results can't conclusively say what exactly makes all humans happy and what doesn't, the growing literature on this topic has found several key themes in how people can go about finding more, long-lasting joy in life.

How much of our happiness can we actually control? Many of us try to achieve happiness by accumulating more things in life that we think will make us happy, like higher income or a stable family life. But as it turns out, there's a scientific reason this strategy won't do us much good.

A pretty large chunk of our happiness is genetic.

Several studies done over the past decade estimate that anywhere between 30 percent and 80 percent of our happiness is dictated by our genes. One large recent study of 20,000 pairs of fraternal and identical twins (widely recognised as the easiest way to separate the differences caused by nature and nurture) found that roughly 33 percent of the variation in life satisfaction is explained by genetic differences.

Other studies suggest that anywhere from 10 percent to 60 percent of our happiness comes from our attitude and overall outlook on life. If you do the math, that means that just a fraction - about 10 percent of our happiness - comes from external things that happen to us, including changes in our career, relationships, or income. So while going after that promotion might seem like it'll make you happy, all that stuff only chips away at the tip of the iceberg.

The 'hedonic treadmill'

A psychological phenomenon called the 'hedonic adaptation' - first coined in the 1970s - states that we all have a base level of happiness that's basically unchangeable - regardless of what happens in our lives. If we get a job promotion, for example, we'll celebrate and feel good, but those emotions are only temporary, the theory goes.

In the early '90s, British psychologist Michael Eysenck likened this constant starvation for more - and more and more - to a treadmill. Consequently, the 'hedonic adaptation' is more commonly known today as the 'hedonic treadmill'. "You're running but you're on that treadmill and you're not getting anywhere in terms of happiness," Zukerman says.

Eventually that boost in happiness you get from a job promotion or marriage proposal will abate, and you'll be back to the same baseline level of happiness you were before the exciting change.

How to make a change for the better

There are lots of science-backed ways we can improve our overall wellbeing and grow happier in the long-run. Here are just a few:

Meditate: Multiple studies suggest that meditating - focusing intently and quietly on the present for set periods of time - can help lessen feelings of depression and anxiety.

Go outside: One study found that a group of students sent into the trees for two nights had lower levels of cortisol - a hormone often used as a marker for stress - than those who spent the same two nights in a city.

Get involved in cultural activities: A study that examined the anxiety, depression, and life satisfaction of over 50,000 adults in Norway offered an interesting link: People who participated in more cultural activities, like attending a play or joining a club, reported lower levels of anxiety and depression as well as a higher satisfaction with their overall quality of life.

Spend money on others: A 2008 study gave 46 volunteers an envelope with money in it wherein half were instructed to spend the money on themselves and the other half put the money towards a charitable donation or gift for someone they knew. The volunteers recorded their happiness level before receiving the envelope and after spending the money by the end of that same day.

Volunteer: In a recent review of 40 studies done over the last 20 years, researchers found that one activity was far more important than the rest for boosting psychological health: volunteering. This activity, the researchers reported, had been found in many volunteers to be linked with a reduced risk of depression, a higher amount of overall satisfaction, and even a reduced risk of death from of a physical illness as a consequence of mental distress.

Conclusion: If you're looking to get a mood boost that'll last you in the long-term, focus on your state of mind in the present, be grateful for what you have, and stop to enjoy it! You'll thank yourself a few minutes - or a few years - down the road.

This article was originally published by Business Insider.

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