One Direction have apparently been banned from eating junk food by their trainer while on tour.
Morgan Spurlock, who is directing the 3D movie about the band, 1D: This Is Us, revealed on Twitter that the lads liked to taunt him by eating McDonald's in front of him - as he was put off fast food when he famously ate nothing but the fast food for a month for his film Supersize Me.
But Morgan added that Harry Styles, Niall Horan, Zayn Malik, Liam Payne and Louis Tomlinson had been warned off eating burgers in a bid to keep in shape for their live shows.
He wrote: "They love eating McD in front of me, but on the new tour they have a trainer who's keeping them off the Big Macs!"
The director - who has been following 1D everywhere for the last four months - revealed the 3D film will include footage filmed by the band themselves.
He said: "The lads have been both in front of and behind the camera. They've been filming each other on the tour bus and on days off, great footage."
Morgan added: "We spend a lot of down time w/ the band, w/ their families and friends. We really wanted you to see what their "normal" lives are like.
"One of the things I really love about the lads is how much they care about and support each other. They really stand by one another."
The director also revealed his footage included "More shirtless moments than you can imagine" and that he is considering some special 'Hair-iel' shots to capture Harry's "flowing locks".