Lizzie Velasquez was once cruelly called the 'World's Ugliest Woman' but now she's starting an inspirational tour to spread a positive message against bullying.
Lizzie is just four stone and has almost zero per cent body fat but her appearance is due to a genetic condition which means she cannot put on weight.
When she was born, Lizzie's parents were told she might not survive, but she has finished university with a communications degree and is now starting a career as a motivational speaker.
The 24-year-old has Neonatal Progeroid Syndrome which causes premature ageing, a wrinkled appearance, and decreased fat under the skin.
Lizzie's condition also means she cannot put on any weight, and despite eating every 20 minutes or so, and consuming thousands of calories a day, she never tips the scales above 4.3 stone.
But now, scientists who have been studying Lizzie for more than ten years believe they are closing in on the gene that causes her condition, which may one day lead to treatments and a cure.
They believe Lizzie, who is the oldest person living with NPS, is offering hope to other sufferers and helping doctors understand how people can survive well into adulthood.
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Lizzie, from Austin, Texas, who is bravely spreading her survival story to help others, explained: "I took a year out after university and now I'm ready to start travelling to give talks in different States.
"I receive so many requests but I have to be careful so my schedule does not become too busy."
Lizzie carefully manages her condition by eating healthy meals regularly, taking rests every few hours, and ensuring she has enough sleep.
If she works a whole day without constant breaks she becomes tired, dizzy, and prone to illnesses which can be serious because she is so small and frail.
Lizzie is also regularly in plaster because of a weak foot which fractures due to a lack of fat and tissue whenever she walks on it too much.
New TLC International series Body Bizarre, which starts on Monday, tells the story of Lizzie's journey into adulthood and reveals the amazing response she receives to her motivational talks.
"My parents raised me to be completely normal. They never told me I was different. The only thing they told me was that I was smaller than the other kids but I was just like them," she tells the audience.
"As I got older I started becoming more aware of why people were staring at me and I got really angry."
But she adds: "I would never tell my parents that I was being bullied."
Lizzie also tells the story of how she discovered a video of herself on You Tube at the age of just 15 which had been cruelly labelled 'The Most Ugly Woman in the World'.
"I was at home online and I saw a picture that looked really familiar. It says Most Ugly Woman in the World, and that's me.
"The number on the bottom - 4,790,642 - is how many views it had when I found it. I felt like someone was literally putting their hand through the computer screen and punching me over and over."
Lizzie describes the cruel comments viewers had made about the video, some of which even asked her parents why they had not aborted her.
Amazingly, instead of causing the devastated teenager to withdraw or hide away, it became the defining moment which helped Lizzie decide to become a speaker to help other bullying victims.
She has already published two books 'Lizzie Beautiful' about the story of her childhood and 'Be Beautiful, Be You' an advice book to help young people deal with low self esteem and abusive behaviour.
Now, as she sets off on a tour to meet teenagers and adults across America, Lizzie reveals her next ambition is to set up a business to prevent bullying.
"My dreams for the future are I continue to help others. I want to create an anti-bullying company something to help kids and adults and teenagers who are struggling and so far my dreams have come true," she said.
Prof Abimanyu Garg, who has been studying Lizzie and other NPS sufferers in the search for the genetic cause, said: "Lizzie is one of the very few people that are known to have this condition.
"They have very little muscle mass, they are limbs look very thin, spindly, and many of these children they die very early in life.
"But Lizzie is 23 years old so she has beaten those odds. I'm very pleased with her progress. She has outstanding courage to face such a severe developmental disorder and live her life fully."
He explained that Lizzie is living proof that there several different types of NPS syndrome and provides knowledge to the scientific community which will offer hope to others.
But despite the chances of a medical breakthrough in the future and the possibility of a treatment, Lizzie insists she is happy with her appearance as it is.
She said: "I would never ever ever change my appearance even if I could. It has taken me so many years to accept who I am and like the person I see in the mirror so I wouldn't change it just to 'fit in'."
World's Thinnest Woman: Body Bizarre is on TLC UK at 10pm on Monday, 11 November.