Diaz, who plays a school mistress in her new comedy film, says she is always in the mood for having sex.
The 38-year-old told British newspaper the News of the World: 'Sex is the sexiest word in the English language. Just the word is sexy to me. There's something to it, don't you think?
'Sex is my favourite sport. And what's the quickest way to get me in the mood?
'I'm always in the mood!'
Cameron has been with baseball star Alex 'A-Rod' Rodriguez for almost a year - although US reports suggest they're about to split.
But the actress reveals she has no intention of ever getting married.
She added: 'I don't think we should live our lives in relationships based off old traditions that don't suit our world any longer.
'I think a lot of people are married to people that they're not romantic with any more.
'We have to make our own rules. I just didn't ever marry anybody that I then had to get divorced from. We break up. We move on.'