At 47 years of age, Jodie is at a crossroads.

Her oldest child Caleb has already left the nest, while her youngest, Isaac, is just two years shy of following suit.

"I am at the stage where I am rethinking [my life]," she says.

"It's like, 'Shit? What do I do?' Once my baby doesn't need me, what do I do?"

According to the statistics, Jodie is right in the age bracket for "middle age misery".

In a newly released study investigating age and wellbeing, researchers developed a U-shaped "happiness curve" across 132 countries — and the lowest point, on average, was 47.2 years of age.

To put it simply, it's when your midlife crisis (statistically) peaks.

"People get realistic, they realise they're not going to be the prime minister of Australia or the CEO of a company, but they're going to be okay," says David Blanchflower, a labour economist and economics professor at Dartmouth College, who led the study.

"You compare yourself to the alternative and realise I have to get real, but also, life isn't so bad."

'What's next in life?'

While Jodie concedes her body is a little worse for wear, and the prospect of an empty nest is daunting at times, she balks at the term "misery".

Rather, she says she is happier and more confident than ever — and unlike her 30s, now has the time and money to explore new opportunities.

"Not knowing what the future brings is pretty exciting," she says.

"I want to travel and see this beautiful country. At times I think, maybe I might work on a cruise ship in five years.

"I am in a bit of a transition. What's next in life?"

It's not a sentiment shared by everyone, however.

For author Cathy Day, who previously wrote about the challenges she encountered when turning 47, it was a period of realisation for her and her husband.

"We realised we were middle aged and headed toward 'elderly'," she said.

"I felt incredibly depressed about that, thinking, Oh, it's happening now. The ageing thing. I'm not young anymore and I never will be again."

After 21 years of being a mother, Jodie is looking forward to the prospect of travelling. ( Supplied )

Social factors like education, marital status and unemployment also play a role in the dreaded midlife crisis, and for people like Gunnar Gudjohnsen-Bollason, ageing can exacerbate those feelings of loneliness.

"I am sitting in my big house talking to myself and a cat that never replies except with an occasional meow," the 47-year-old says.

"No woman, no children, always working my butt of... yes, there is a middle age misery [peak] at 47."

You won't be miserable forever

If these figures are sending you into an existential spiral, fear not — things do eventually get better.

While younger people were considered among the happiest of the cohorts, according to Professor Blanchflower, wellbeing makes a marked improvement as people approach their 60s.

"I think there are three things why their happiness goes up," he says.

"The first is, they're alive. Second, they have a job and third, they're healthy enough to have a job."

The study's author David Blanchflower, now in his 60s, says his happiness is only trending upwards. ( dartmouth.edu )

So what do you do until then?

According to Professor Blanchflower, you embrace the midlife crisis — in all its eccentricities.

"I went through a mid-life crisis and bought a snowmobile. A large motorised vehicle speeding off into the stratosphere," he laughed.

"What do people do? There's all kinds of things that people do. It's a tough time."