James Franco has lost advertising deals because the companies were unhappy with him backing films about gay sex and the porn industry.

The Oz the Great and Powerful star recently produced Kink, a documentary about a hardcore porn studio, and directed Interior: Leather Bar - which features gay sex scenes - and he admits working on such daring projects is always a "risk" because of how it impacts other elements of his career.

"It is a risk. The films I have did get a lot of praise, but I did get some pressure from other areas. I was supposed to do a commercial with this company and they pulled out because they weren't happy, they didn't like the subject matter of the films. It was a champagne company. You'd think they'd be grown up enough but I've had it happen with this company and a car company as well," he admitted.

However, the 34-year-old actor insists he will never let the decisions he makes on projects to be influenced by how they will impact on his later career: "If I'm at the threshold of doing a project and the question comes up, 'Will this be harmful to your career?,' I never want that to be a deciding factor."