"I'm not obsessive about [dieting]," Moore, 27, told PEOPLE at the Tangled press event held at Disneyland recently.
"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," she says.
But Moore, who wed musician Ryan Adams last year, hasn't always been so easy-going. She admits in the past she has sometimes placed too much emphasis on her weight.
"[There have been times] when it's the first thing on my mind all the time," says the actress who voices Rapunzel in the new animated film, which opened Nov. 24. "I'm so affected and driven by that diet and what I'm eating and how much I'm exercising."
No longer stressing over being a certain weight, Moore says she's developed a much more relaxed perspective about being fit.
"I've just realized in time that if it's a constant thread in the background of my life," she says, "that's when I'm the happiest and that's when I feel the best about myself."