(Telegraph) - Twitter and Facebook are more addictive than cigarettes and alcohol, researchers claim. Resisting the urge to check social networking sites for updates is more difficult than turning down a drink, according to a study of people's everyday desires. The survey of 250 people found that sleep and sex were the two things people most longed for during the day, but that the urges to keep on top of social networks and work were the hardest to resist. In contrast alcohol and tobacco prompted much lower levels of desire despite their reputation for being addictive.