Are these the most extreme plastic surgery addicts ever?

Celebrities and movie stars are often quick to deny they've had work done to perfect their appearance, but that is not the case for the subjects of a brand new All 4 series, Plastic and Proud.

The show features Swedish glamour model Natasha Crown, whose aim in life is to have the biggest bum as possible.

To achieve a derrière that makes you stare, Natasha gorges on chocolate sundaes and huge meals in an attempt to deliberately pile on the pounds for a fat transfer that will make her six foot rear even bigger, reported the Daily Mail.

"I was 20 when I had my first procedure and yes, I would say I'm obsessed," she said.

"The first thing I do in the morning is go to the mirror and look at my bum.

"Maybe I have body dysmorphia or something but I don't feel like it is even that big. I definitely want bigger."

Natasha Crown earns a living by selling her videos and photographs to big bum enthusiasts. Photo / Getty Images

The 24-year-old grew up as a happy child in Gothenburg and says she was always very outgoing and popular.

"When I was a teenager and my body started to change - I got boobs, I got a bum. I just loved my body so much.

"Since then I have had three butt lifts as well as boob jobs and I also have [lip] filler and lots of other procedures.

Natasha Crown gears up for a consultation on what will be her fourth bum lift surgery in four years. Photo / Getty Images

"I just love the feel of having a big bum. When I walk, I feel all the jiggling, jiggling, jiggling and I start to feel horny with myself.

"That is the best feeling I think. My bum makes me feel sexy and makes me feel powerful."

But not everyone is as thrilled with Natasha's life choices as she is.

Her parents have regularly pleaded with her to stop altering her body, worrying that her pursuit of the perfect body is doing untold damage.

Pixie Fox is on a cosmetic quest to look like a living cartoon in LA. Photo / Getty Images

She said: "They think about my health and tell me to think about the future, will I ever have a family of my own and things like that.

"It is difficult for them to see me change. Sometimes they have been very cruel and said things like, 'you look like a cow.' they don't understand why I am doing this and I say to them: 'how can you speak to your own daughter like that?'

"Eventually, I just had to say: 'Ok, you think that, but I am going to continue because this is for me and it makes me happy.'

The documentary follows Natasha as she visits her plastic surgeon, Dr Berne, for a consultation on what will be her fourth butt surgery in four years.

Bryan Ray is obsessed with looking like Britney Spears. Photo / Getty Images

Dr Berne said: "Obviously, you have to be careful that you do not perform surgery on anyone who maybe needs psychiatric help or is vulnerable but you look at Natasha.

"It is obvious she has a strong mind and she knows what she wants."

"Curvy Natasha's shapely rear has attracted thousands of fans online and she now earns a living by selling her videos and photographs to big-bum enthusiasts.

She said: "I never knew it was possible to make money from having a big bum but I love my job and I never want to do anything else."

Neven Ciganovic, 47, has had countless surgeries in his quest to maintain a youthful appearance. Photo / Getty Images

The series also catches up with self-confessed plastic surgery addict and Croatian TV personality Neven Ciganovic. The 47-year-old is on a quest to remain youthful looking forever - and is spending a fortune on extensive surgery to do so.

Neven said: "I had my first surgery when I was 22 and I just couldn't stop. My goal is to look good forever."

After losing a lot of weight in his teens, the reality star became obsessed with how he looked.

Pixie Fox had six ribs removed to achieve her tiny waist. Photo / Getty Images

He explained: "I've had three nose jobs, silicone plumping in the lips and I have twice had cheek implants.

"I just want to stop this raging. I want to look 47 forever."

The series also tells the stories of star, a former stripper and dominatrix from Birmingham who travels to Istanbul for extensive surgery.

Pixie Fox. Photo / Getty Images

Pixie Fox, a self-confessed plastic addict whose quest to look like a living cartoon has seen her have countless surgeries including the removal of six ribs also stars.

And Bryan Ray, a 32-year-old whose obsession with Britney Spears has seen him spend more than £80k on transformative surgeries and procedures.