Kim Kardashian started crash dieting when she was just 13.

Kim Kardashian (left) and Nikki Lund as kids (image via Nikki Lund/Rumorfix).

It’s no secret Kim Kardashian is conscious of her appearance.

The 34-year-old reality TV star famously uses apps to edit and enhance her Instagram snaps, has a beauty line in her family’s name, and regularly spruiks waist training as a means of keeping in shape. As a woman who is constantly in the public eye, and who has her every movement filmed and photographed, you can sort of understand this fixation.

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However, it seems Kim’s hyper-awareness of her image began when she was just a kid; 13 years old, to be precise. One of Mrs Kardashian West’s childhood friends, Nikki Lund, recently claimed she and Kim began experimenting with popular crash diets in their early teen years.

"At 13, we started to become more aware of ourselves. We began wearing make-up and started dieting," the fashion designer, 32, told Heat magazine. "It was mostly the Atkins and the South Beach Diet. We did the Cabbage Soup Diet and we'd be there boiling great big vats of cabbage. We were like, 'Yes, we're going to be thin'."

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Lund has also previously said Kim would ask for "a burger with no bun" to avoid taking in carbohydrates.

The thought of a 13-year-old taking dieting this seriously is sad and shocking but it's also "very common", according to clinical psychologist and director of Shape Your Mind, Dr Olivia Patrick. [post continues after gallery]

"It is becoming more and more common for primary school age children (and sometimes even younger) to be very concerned with their appearances, in particular a fear of being fat," Dr Patrick explains.

Mission Australia's annual national youth survey has found body image is one of the top three concerns among young Australians, and according to the Butterfly Foundation, previous research has found 75% of high schools girls feel “fat” and want to lose weight with 90% of 12-17 year old girls are on a diet.

There are several factors that can contribute to girls developing a hyper-awareness of their body and image.

Although well-intended, it seems Australia's ongoing campaigns to combat obesity — including the 'healthy lunchbox' movement in schools — have indirectly exacerbated this. "We have children as young as three asking their parents if they’re fat and need to go on a diet," the Butterfly Foundation's CEO Christine Morgan says.

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"In the current climate of fear surrounding childhood obesity, parents are often paying a lot of attention to and commenting on their child’s weight," Dr Patrick adds.

Genetic vulnerability to depression or anxiety disorders can also play a role, as can parental behaviours; dieting or negative body attitude exhibited by mothers can have a bearing on how girls think of their own bodies.

Unfortunately, dieting from a young age can continue to have a negative impact on women as they grow up. Disordered eating is a potential outcome — this was sadly the case for Nikki Lund, who told Heat that dabbling in fad diets in her teens eventually led to her developing anorexia.

"Dieting by its very nature involves an increased preoccupation with food and weight, and implies a lack of trust in one’s own body signals," Dr Patrick explains.

"If this starts at a young age, the individual will have very limited or no experience of being able to trust themselves to respond appropriately to hunger and fullness, setting them up for a lifetime of dieting and possibly disordered eating. While most people who diet do not go on to develop an eating disorder, many do develop a disordered relationship with food; and almost all eating disorders begin with a diet."

Although she seems quite body confident now, Kim Kardashian has admitted this acceptance has been a long time coming. In an interview with Elle UK last year, she said, "It’s taken me a long time to be happy with my body and for my confidence to grow to what it is today. I grew up when the body to have was the tall, slim, supermodel one, like Cindy Crawford’s. No one looked like me."

However, like many women, it seems the mother of one still struggles with her body confidence from time to time. This was particularly evident during her pregnancy, when publications and trolls mocked Kim for gaining weight (which is ludicrous considering that's exactly what a pregnant body is supposed to do).

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"I’d think God was doing this for a reason. He was saying: ‘Kim, you think you’re so hot, but look what I can do to you.’ My body just went crazy. After five months I swore I’d never get pregnant again," Kim told Elle.

"I got so huge and it felt like someone had taken over my body. I’d be sitting there, nearly 200lbs, crying and swearing this will never happen again, and sometimes I’d actually be laughing about it.”

The Butterfly Foundation's Christine Morgan says it's important for women to be aware of the dangers and unsustainable nature of dieting, and to understand that their worth is not inextricably tied to their weight.

"We must remember that healthy eating, healthy exercise, and a healthy approach to all appetites both physical and emotional underpins long term, sustainable well-being," Morgan says.

"For those that find this challenging, it is imperative that we do not add to the pressures they are under by allowing them to believe their worth as a person is tied to their looks, their size, or their shape."

Anyone needing support with body image or eating disorders is encouraged to contact the Butterfly Foundation National Eating Disorders Supportline on 1800 33 4673 (1800 ED HOPE).