21 year old Lizzie Velasquez, from Austin, TX, suffers from an extremely rare syndrome that stops her from gaining any weight. Doctors don't even have a name for this disorder yet, which only 2 other people in the world are known to have. Lizzie's highest weight ever was only 62 lbs.

See more here:
http://www.telegraph.co.uk/health/healthnews/7858664/The-girl-who-must-eat-every-15-minutes-to-stay-alive.html

Her website:
http://www.aboutlizzie.com/