'Up to five deaths' caused by drinking game Neknominate
22 February 2014 Last updated at 13:40 GMT
Social networking sites Facebook and Twitter should introduce warnings over the drinking game Neknominate, councils in England and Wales have said.
The game, which involves people filming themselves downing alcohol and then nominating someone else to continue, has been linked to several deaths.
Professor Mark Bellis from the UK Faculty of Public Health spoke to BBC Breakfast's Naga Munchetty and Charlie Stayt about the dangers of the game.