The 36-year-old actress talks her younger self in the interview revealing that, "I'm not so different than I was at 20.
"I still buy too many jeans... I don't stay stuck on anything too long. I mean, like, any emotion."
Holmes shot to fame after appearing in Dawson's Creek where she played girl-next-door Joey Potter. While her six-year marriage to Tom Cruise has ended she has her daughter, 8-year-old Suri, to think about as well as endless new career opportunities.
Her latest project? She's starring in and producing the film based on All We Had by Annie Weatherwax and she's the face of the Olay Best Beautiful campaign.
On being in the limelight she says, "I think that it's a very interesting time for artists right now because of social media and camera phones. I don't think you ever know how you'll be portrayed. Any story can attach itself to your image.
"I don't pay much attention because I'd spend the whole time worrying. I just don't go out much to avoid it."
On being a woman and having them in her life? "Women are complicated, in a beautiful way, and they have lots of different roles. I'm inspired by the community of women it takes to help one woman succeed. It's important to be supportive and have people you can call at 3am."
Read the full interview in February's issue of Red on sale from 2 January 2015.
LOVE KATIE'S STYLE? Flick through this gallery to see just how far she's come in the wardrobe department.