Julia Louis-Dreyfus is dishing about her secrets to a rock hard bod at 48.

"I have to work at not being fat," she tells Shape magazine in its April edition. "I'm always trying different things to see what sticks."

The actress has developed a reward system to keep herself on track. "I feel like I deserve a treat when I work hard," she says. "It's important to give yourself a little of what you really want so you don't feel like you're in food prison."

She does confess to a sweet tooth -- and an achin' for some bacon! "I have a chocolate drawer in my desk where I keep treats at all times," she says. "As long as I can have one or two pieces, I'm fine." But she won't keep her favorite food around. "My biggest food vice is bacon," she confesses. "In fact, I don't keep bacon in my house -- that would be way too tempting."