'Sex and the City' star Kim Catrall has been dieting since 1974

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."