Rooney Mara is drawn to ''natural beauty''.

The 'Side Effects' actress admits she doesn't wear much very make-up and thinks she would be ''horrible'' at applying cosmetics herself.

She said: ''For me, natural beauty is something I've always been drawn to. I still don't really wear make-up in my everyday life and I would be horrible at even trying to do it to myself!''

With her fondness for looking natural, it's no surprise Rooney doesn't have many go-to beauty products, and instead believes her radiant skin is a reflection on her diet.

Quizzed about her skincare product of choice, the fuss-free star said: ''This is going to sound so simple, but sunscreen! I always wear sunscreen. I also find that what you eat is the best beauty secret; it sort of starts from the inside out.''

The 28-year-old beauty - who is the face of Calvin Klein's new Downtown perfume - also reveals that the fashion house's designs reflect her own simplistic style.

She said: ''The Calvin Klein collection is really quite similar to how I dress in my personal life. It's very minimal and clean and comfortable, but very modern and chic at the same time.''

Rooney recently filmed a glamorous campaign for the new perfume, which was shot by her 'Girl with the Dragon Tattoo' director David Fincher.