The 56-year-old actress - who is best known for playing Samantha Jones in `Sex and the City` - admits it is a struggle for her to retain her slender shape, particularly as she gets older. She said: "I joke that I`ve been on a diet since 1974, which is basically true. "I like to eat, and my body type is not naturally this thin, especially at this age. I have a big appetite." Kim admits she is astonished that she still lands roles as a "sexy siren", as she thought once she hit 40, the sort of parts she would be offered would change. She told the May edition of Woman & Home magazine: "When I hit my 40s I thought, `I can`t play a sexy siren any more.` Almost 20 years later, it`s still going on." And despite being single since splitting from chef Alan Wyse in 2009, the blonde actress insists she doesn`t try to intimidate guys with her image and success. She added: "If my accomplishments frighten someone it`s nothing to do with me - that`s to do with them."