If you’re wondering how Catherine Zeta-Jones manages to keep her skin so dewy at 46, she’s more than happy to share her secret. The Hollywood star has told how she uses argan oil to moisturise her complexion, saying she ‘saturates’ her face with it to keep her looking youthful. Although the product is becoming increasingly popular in the kitchen for its supposed health properties, Miss Zeta-Jones, like many women, prefers to make it part of her daily beauty regime. During a webchat yesterday, the star said her hectic workload was taking its toll on her appearance and leaving her complexion as dry as a potato crisp. She said: ‘I’m finding, just from travelling from New York and being in heated hotel rooms, my skin feels like a Walker’s crisp at the moment, but I’ve been using some argan oil just to saturate my skin at night, so it has some nourishment as I sleep, to start the day a little bit more hydrated.’ The Oscar-winner, who is in the midst of a promotional tour for the new Dad’s Army film in which she plays a glamorous journalist, added: ‘The real hydration comes from within. You can never drink too much water. No diet sodas!’ She added: ‘I think happiness is the best tonic for keeping us youthful. Being happy with who you are inside radiates on the outside.’ The oil is produced from nuts of the argan tree, which is native to Morocco and has long been used by Berber women to treat ailments such as dry skin, acne, wrinkles, joint pain and even stretch marks.