The 8 habits the happiest people in the world swear by – how many are you ticking off?

WHETHER or not you feel happy might not always feel seem something that's within your control.

But according to longevity guru Dan Buettner, happiness can be tied to the small things - like what you eat for breakfast or the number of hours you sleep each night.

The author and National Geographic fellow has made career out of studying the world's longest living people, coining the terms Blue Zones to describe five regions across the world where people live to a ripe old age.

These are Sardinia, Italy; Ikaria, Greece; Nicoya, Costa Rica; Loma Linda, California; and Okinawa, Japan.

In a uploaded to his , Dan turned his focus to habits of the world's happiest people.

He claimed many of them do eight simple things that lift their mood daily and keep them smiling long-term.

From taking a nap to talking to a friend daily, here are eight lifestyle tweaks you can make to feel merry.

1. Sleep at least 8 hours

When it comes to health and wellbeing, sleep seems to be at the core of it - and happiness is no different, according to Dan.

"The happiest people sleep between eight and nine and a half hours a day," Dan claimed.

"If you're sleeping six hours, you're about 30 per cent less happy."

Experts at echoed Dan in saying that sleep and mood are 'closely connected'.

They said: "Poor or inadequate sleep can cause irritability and stress, while healthy sleep can enhance wellbeing."

Dan's recommendations for the amount of sleep you should be getting are slightly that those set out by the NHS, which recommends adults get seven to nine hours of sleep nightly.

2. Eat a plant-based breakfast

Turns out starting the day right can have wide-reaching effects.

Dan advised you begin your morning with a plant-based breakfast - that means staying away from meat and dairy products.

The longevity guru also suggested you stay away from overly sweet and fatty foods in the morning.

He explained: "If you eat a big fatty breakfast or sugary cereal, you're going to be hungry [by] midday, you're going to have less energy throughout the day."

3. Socialise

Socialising daily is key to be being happy, according to Dan.

"Make sure you have coffee with a friend, you have lunch with a friend," he suggested.

"You want to make sure to engineer in four to five hours - or six if you can - of social interaction with people you like."

Studies suggest that loneliness can do more than affect your mood - it can also take a toll on your health, increasing your risk of dementia, heart attacks and strokes.

4. Volunteer

Dan suggested you "find a little time to give back everyday".

"Worldwide, statistically speaking, volunteers are happier than non-volunteers," he claimed.

Research by the University of East Anglia suggested that volunteering was associated with improved life satisfaction, increased happiness and fewer symptoms of depression.

5. Nap

Dan's fifth suggestion for happiness was simple: "Take a nap."

Research conducted by the University of Hertfordshire in 2017 showed that taking a power nap in the day could be the secret to happiness.

Psychologist Prof Richard Wiseman said: "Previous research has shown naps of under 30 minutes make you more focused, productive and creative.

"These new findings suggest you can also become happier by just taking a short nap."

6. Work part time (if you can)

Dan went on to say that working part-time instead of full-time could make you happier - that is, if you have the means to.

"We know from every place in the world [that] people working less than about 35 hours a week report the highest level of happiness," he claimed.

"Of course, you need to make enough money to cover your basic needs."

Trials of four-day work weeks have in fact found that working less could make us happier and healthier.

7. Have faith

"Belonging to a faith - doesn't matter what the faith is - stacks the deck in favour of happiness," Dan said.

A found that actively religious people were more likely than their less-religious peers to describe themselves as “very happy”.

8. Limit TV and social media

Many of us crave a daily fix of social media scrolling or watching our favourite TV show.

But Dan said of TV and social media: "It seems that about 30 minutes a day of each is optimal."

Research into kids' screen time found that more time spent in front of TVs, video games and social media boosted the chances of mental health issues in children aged three to six.