Joni Edelman knows that 'thin equals happy' is a fantasy - and wants more people to understand it, too.

The mother-of-five from California has written an incredibly personal essay about how her quest to retain her picture-perfect size 4 body was not only making her unhealthy but miserable.

A full-time nurse, Edelman was 35-years-old with three kids and weighed just 123 pounds because of her obsession with counting calories and working out.

It was a condition she came to refer to as 'exercise bulimia'.

Before and after: Joni Edelman says she put herself through hell to maintain her size 4 figure. So she decided to stop, and said she has never been happier

Flashback: Edelman, seen here on vacation with her husband, made a decision to stop torturing herself with diets and exercise and enjoy herself

Happier: The mother-of-five has not revealed what she weighs now, but was 123 pounds at her smallest

'If I ate a cookie I needed to run 3 miles,' she told The Chicago Tribune.

'I was thin.

'And when I looked in the mirror, I still saw flaws; ''My stomach is saggy because I've had kids. My breasts have lost their volume.''

'There was no satisfaction in the thinness.'

Edelman's essay first appeared on Ravishly.

In it she explains how she kept her diet to a measly 1,000 calories a day.

'(I maintained being a size 4) by running 35 miles a week, by sleeping an average of three hours a day, by counting every bit of food I ate, down to a single cherry tomato, by writing and tracking my weight every day for a year, by running the stairs of the hospital during my 12-hour shifts, by losing my period,' Edelman wrote.

Obsessive: Edelman (left) says she was living off a measly 1,000 calories and running 35 miles each week to retain her stunning figure

Better off: The mother-of-five says there is a 'stillness, joy and peace' to her life now that she's never had

'Exercise bulimia': Joni Edelman would even work out during shifts at the hospital, running up stairs

'Being a size 4 made me a lot of things.

'It did not make me happy.

It made me obsessed with my workouts, with how much time I could fit in at the gym between taking care of three small kids and working 12-hour overnight shifts.'

Edelman goes on to say she felt compelled to write about her situation in order to make people aware of what she calls a dangerous stereotype.

'This isn't to say that thin people aren't happy (duh), but this is to say that being thin is not: A. A cure for sadness or B. A guarantee of happiness,' Edelman wrote.

'It is to say this: Happiness does not require thinness. Fatness does not presume sadness.'

Edelman, who has bipolar disorder, said the effects of her new approach have been dramatic, particularly mentally.

Family first: Edelman's change of perspective has given her more time with her husband and five children

All-smiles: Edelman felt compelled to write about her situation to call out a dangerous stereotyple that 'thin equals happy'

'There is a stillness, a joy, and a peace I've never had.

'It's worth 10 pounds.

'Ten pounds are insignificant when compared to my willingness to let some things go, to sit with my kids, to sleep.

'I'm happy.

'I'm fat and I'm happy.'