The singer-turned-actor, 30, is starring opposite Amanda Seyfried in his new movie about what people will do to stay young.
Asked if he would do anything to stay looking youthful, he told UK newspaper Daily Record: 'In my younger days, I looked ridiculous, so no. I've tried to forget the way I looked. Seriously, I like myself more now than I ever have.
'I think it's because you just get to a point where age becomes attractive to you in a way. When you accept the inevitability that you are ageing, that you are getting older, I think it becomes a thing you settle into.
'I have no desire to be young again. I'm still young. I still feel very young and I'll always feel very young, but I'm excited to progress.'