United States president Barack Obama took time during a dinner on Saturday to show off his moves to .
Valeria Levitin, 39, developed the eating disorder as a teenager after years of her mother weighing her as a child.
The Daily Mail reports she was teased at school about her weight and told she was 'too fat' to be a model.
Now, she is horrified by the letters she receives from girls wanting weight loss tips.
Instead, she warns them that her emaciated figure should be a severe warning about the dangers of extreme dieting.
She describes being anorexic as "lonely, unattractive and repulsive for the people around me".