Speaking at the Tangled press event held at Disneyland recently, Mandy told People.com: 'I'm not obsessive about [dieting].
'If I want to have a burger and fries like I did the other night in the park, then I'm going to do that because that's okay.'
But Moore says she hasn't always been so easy-going and has previously worried too much about her weight.
She added: '[There have been times] when it's the first thing on my mind all the time.'
The actress, who voices Rapunzel in the new animated flick, added: 'I'm so affected and driven by that diet and what I'm eating and how much I'm exercising.'
But Mandy has more recently taken a different approach to keeping fit.
She said: 'I've just realised in time that if it's a constant thread in the background of my life, that's when I'm the happiest and that's when I feel the best about myself.'