The 33-year-old mother of two said she plays sexy characters on-screen but has never slept her way through Hollywood, reported Contactmusic.
"I never slept my way through Hollywood, so I never felt like I compromised. Apparently people do it, I didn't. I felt like I never compromised myself because I'm a prude. I don't know. I grew up Catholic. In my head I'm always thinking, 'Oh God, can my grandma see this?'," she said.
Alba, who started her film career aged 13 before getting her big break appearing on the remake of TV series 'Flipper' in 1995, has daughters Honor, five, and Haven, two, with husband Cash Warren, which she says has changed her attitude to her diet and made her stop trying to be perfect.