WEBSITES that feature child pornography are illegal. Yet those that promote child starvation - the pro-anorexia (or pro-ana) sites - are not. They portray eating disorders as a lifestyle choice, give tips about hiding weight loss from parents and doctors, and incite users (mostly girls and young women) to boast about how little they eat. Tumblr, a blogging platform, blocked pro-ana blogs in February (searching for them redirects users to a helpline). Since then two photo-sharing sites, Instagram and Pinterest, have started removing "thinspirational" images. Facebook has been deleting pro-ana pages since 2008. But ANAMIA, a French research project, claims that the bans may not work. Site owners simply remove keywords or migrate to other services. Susan Ringwood of B-eat, a British charity, says pressure may drive anorexic networks underground, stoking their sense of persecution and making it harder for help to reach them. Bans may also hit sites that offer help. New research by the University of Suffolk finds that anorexics go online to meet like-minded teens and to engage in "girly chit-chat about boyfriends and books," says the study's author, Emma Bond. They fear losing the sense of belonging that goes with the forums. Proud2BMe, a Dutch-American website promoting body confidence, offers the support of pro-ana sites without the toxic bits. Founded in 2009 by a recovering anorexic, it is now one of the Netherlands" most visited mental health sites.