There's nothing wrong with wanting to look good. According to her, she's "been spending all day, every day, in weapons training... shooting guns, weightlifting, kick-boxing..." This all sounds like she's being really healthy, but with all that expenditure of energy, someone is still telling her she is not allowed to put sugar in her tea?
This hoax may purport to play on our collective gullibility and Twitter-trigger happiness, but it actually plays straight into the mental vulnerability of our society's young women, who are already overly bombarded by images of hollow cheekbones, washboard stomachs and thighs that don't meet. It is hardly newsworthy that this hoax had us collectively fooled.
Tumblr is fairly notorious as a platform to go find your images for anything to do with self harm and so called 'thinspiration'. These kinds of resources have been labelled by professionals and campaigners as damaging for many years now and their consequences have been the base of much fierce debate.