"We give our best on stage every night! And for 1 person to start a rumour! Just messes it all up."
However, it seems the rumour begun after a gif appeared of Niall and bandmate Louis Tomlinson pretending that there was vodka in their water bottles, with the Kiss You hitmaker later explaining that they were NOT drinking alcohol on stage.
Ah now I get why people are saying it ! Hahah! Me and @louis_tomlinson do that every night! Pretend there is something in the water bottles