The 38-year-old says she feels 'stronger' and more 'liberated' as she approaches her 40s.
She told British Metro newspaper: 'I love getting older. In my twenties, I wanted to be in my thirties. Now I'm not afraid of my forties. The other day this kid of 22 asked if I was afraid of 40. I was like: 'Don't be afraid, son!'
'Life is so much better as you get older. You're liberated from so many things. I feel stronger, more capable, more fulfilled than when I was 29, 30, 35.'
Despite getting older, Cameron manages to show she's still got it in her new film Bad Teacher.
Talking about her sexy car-washing scene in film, in which she is seen wearing extremely tiny shorts, the actress added: 'By the way, sliding around on a wet car is very dangerous. Do not try it.'