Janet Jackson in New York City May 10
05/14/2012 at 02:00 PM EDT
After years of yo-yo dieting
, Janet Jackson
is finally at the size she wants to be. Just don't ask her how many pounds she's dropped.
"I don't know how much weight I've lost, only because I stay away from the scale," Jackson told PEOPLE at Marco Glavianos "Supermodels" exhibit in New York recently.
"I don't think [stepping on the scale] is healthy. You're setting yourself up to fail and women's bodies fluctuate every month – certain time of the month in particular – we bloat a great deal," she says.
This time around, Jackson – who turns 46 on Wednesday – is battling the bulge with NutriSystem. She became the company's spokeswoman in December.
"It works, point blank," says Jackson. "You don't have to starve yourself getting there." The singer adds that she isn't depriving herself of her favorite foods – whether they're on the plan or not.
"I love caramel apples! NutriSystem doesn't have that, so that's probably my cheat food. I go out to dinner with friends [too], but then I just get back on it. It's about maintenance."
Still, it's not just watching what she eats that helps her maintain. "If I'm getting ready for something like a tour, I work out six days a week. I like to switch it up. I may go for a run or bike," she says.
As for whether she's reached her goals, Jackson says, "I'm really happy with the way that I feel at the moment. I feel very good, and it's been a long time since I've felt this good."