08/19/2008 at 01:00 PM EDT
Jennifer Love Hewitt is looking forward to turning 30 – but if she could turn back the clock, she would have spent more time showing off her figure.
"I wish I had been nude from the time I was 12 until I was 28. I looked great!" the Ghost Whisperer
actress, 29, tells Health magazine
in its September issue.
"I so wish I had listened to my mom and grandma when I was 18 and would complain about some little tiny bump or feeling bloated," says the star, who is engaged
to Scottish actor Ross McCall. "I used to scoff and say, 'No, I feel fat today!' Now the joke's on me."
Hewitt found herself defending her figure
last year when several Web sites criticized her weight after she was pictured vacationing in a bikini.
These days, she's spreading some body image love to her younger peers. "I want to tell all young girls to walk around in bikinis all summer, because there will be that one day in your twenties when you'll eat a hamburger and actually see the hamburger on the side of your leg," she jokes.
The next milestone for the actress is turning 30 this February – and she can barely wait. "I'm so excited! It's my dream age," she says. "I don't know why but, literally since my 12th birthday I've wanted to turn 30."
2007: Jennifer Love Hewitt takes her body-image battle to the cover of PEOPLE
Look back at Jennifer Love Hewitt's first PEOPLE cover