James Franco insists sex is a ''huge'' part of life.

The 34-year-old actor - who portrays Playboy founder Hugh Hefner in 'Lovelace', a biopic of tragic porn star Linda Lovelace - insists even people who perceive themselves as ''chaste'' are still influenced by sexuality because it is part of human nature.

He said: ''Sex and sexuality are such big parts of our lives - the ways that we define ourselves, the ways that we interact with each other.

''Everyone thinks about it. Everyone knows about it. Even if you insist on living an incredibly chaste life and you're chaste in your thoughts, that's a conscious and concerted effort to keep sex from your thoughts. So you're still engaging with sex even if it's in a negative capacity.

''It's a huge part of our lives. It's part of being human.''

James has also been producing 'Kink', a documentary about the world's largest producer of BDSM (Bondage & Discipline Dominance & Submission Sadism and Masochism) pornography and admits it is tricky to explore the subject thoroughly without upsetting censors.

He added to MTV News: ''It's hard to put certain kinds of sex in film. Now, I could sort of understand that if it wasn't so easy to put other kinds of things in film, like violence. Obviously, there's some weird standard here that is just illogical.''