How to live healthfully is no mystery for CSI: Crime Scenes Investigation star Marg Helgenberger. Nope, the 49-year-old actress knows exactly what it takes to keep in fighting shape.

Helgenberger meditates every morning, does yoga twice a week, reads for relaxation, and eats lots of yogurt, fresh berries, fresh papaya, sliced turkey, salad, and cheeses. A typical Helgenberger menu goes like this: Smoothie made with yogurt, rice milk, and fresh fruit, followed by a lunch featuring tuna or turkey sandwich or a salad topped with protein, and then fish or chicken with veggies and salad for dinner.

Guilty pleasures? Yep, she's got some. She loves chocolate chip cookies, Girl Scout thin mint cookies, fried chicken with macaroni and cheese, and a good steak now and then. It's all about moderation and balance for this woman who has a very sensible approach to aging: "I certainly want to look the best I possibly can," she says. "But I keep coming back to this theory that you have to work with what you've got and grow older gracefully."

What are your guilty pleasures? More important, though -- what are your secrets for keeping fit for the long haul?