Justin Bieber has become the first person to get 40 million Twitter followers.The 'Beauty And A Beat' hitmaker - who joined the micro-blogging site in 2009 - has beaten other stars, including Lady Gaga and Taylor Swift, to the milestone with his @justinbieber account. He wrote: "#40millionstrong" before later adding "#40millionBeliebers - thank you. I love u. #grateful (sic)."Justin's Twitter record comes soon after 'White House Down' actor Channing Tatum revealed he was worried about the 19-year-old singer.The 33-year-old actor thinks the 'Baby' hitmaker - who was discovered at the age of 14 - found fame too young and hopes he doesn't go off the rails like many child stars do.He said: "I do believe that whatever age you become famous, you end up staying that age."I worry about Bieber, man. That kid's wildly talented. I hope he doesn't fall down into the usual ways of young kids because it' so hard for someone to be responsible when they're not asked to be."