Credit: Jamie McCarthy/

Cindy Crawford may be 44 years old, but she still has a supermodel bod. How does she do it?

"Smoke and mirrors!" she jokes to

The former model does admit that she has a few tricks up her sleeve to stay in tip-top shape.

"It's a combination of a lot of things," she told Us while hosting the DIFFA Dining by Design Gala in NYC Monday. "I don't smoke, I don't take too much sun on my face -- all those things. If you keep doing them enough over the years, they add up."

Plus, she says "the biggest part" of her success has been staying fit for more than 20 years.

"It's not that I work out every day, [and] I'm not ever on a diet -- I just eat healthy," she says. "I'm never off the wagon, so I never have to get back on the wagon. I think it's about maintaining a healthy body weight."

The mother of two children -- Presley, 10, and Kaia, 8 -- tells Us that it's not just about an exercise regimen.

"Just being happy and doing work that you love -- self-confidence is really what's attractive in people, and I think that that comes out," she says. "If you're happy and you're doing work that you enjoy -- for me it's about being a mother -- that comes out in how I look."