"The experience of growing older is that you become more introspective," the 37-year-old actress tells the July issue of InStyle magazine, which hits newsstands on June 18. "You learn who you are and what you want."
One of the biggest lessons Diaz -- who stuns on the cover in a white open-back dress and glowing skin -- has learned is that the woman she is today has little in common with the silly girl she was 10 years ago.
"When you're in your 20s, you have no idea what the hell's going on or who you are or how the world works," explains the blonde beauty, who co-stars with Tom Cruise in the action-comedy "Knight and Day," which opens in theaters June 23. "Wisdom is really underrated."
Indeed, these days, the former model isn't focusing on making her skin look better but rather feeling better in her skin -- wrinkles and all.
"We are obsessed with youth, with physical youth, what we look like and what happens to our bodies as we get older," says Diaz, who was photographed for InStyle by Michelangelo Di Battista.
"We forget what happens to our souls, our minds, and our actual human experience."
Sigh. Easy to say when you look like Cameron Diaz, make movies with Tom Cruise, and date superstars like Justin Timberlake and Alex Rodriguez.
Visit InStyle.com to read more of the star's interview, see how her look has evolved over the years, check out the actress's red carpet style, and try on a Diaz 'do.
In related news, see how Cameron Diaz and other stars are bringing short-shorts back.