With a wife almost half his age it is no surprise that Michael Douglas has been desperately trying to hold back the sands of time.

As his hair turned increasingly grey the Hollywood star had regular highlights in the past to keep it a more youthful blonde.

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But these days it seems he is finally ready to start looking his age - at least as far as his hair and eyebrows are concerned.

Pictured leaving The Ivy restaurant in Beverly Hills with his 37-year-old wife Catherine Zeta Jones, Douglas had reverted to his natural grey.

Wearing a cream jacket and lilac top with purple trousers and sunglasses he walked in from of Miss Zeta-Jones who looked stunning in a low-cut black dress and diamond necklace.

One onlooker said: "It was weird to see him with grey hair. He looked his age but that's better than dying it grey when you're over 60."

Over the years speculation has been rife about Douglas's enduring good looks.

The actor, who turned 62 in September, has denied having any cosmetic procedures despite reports that he had paid £7,000 to "freshen up" his features with a face and eye lift before his marriage to Miss Zeta-Jones.

And last year, when the couple, who have two children, Dylan, six, and Carys, three, holidayed in Barbados, the Fatal Attraction star was seen with two bleeding scars in front of both ears.

His publicist denied surgery, insisting he had had two benign lesions removed from his face.

Later that week he appeared on the beach showing off a newly toned physique, prompting speculation he had also had liposuction a and a tummy tuck.

And this summer he was spotted with a remarkably smooth wrinkle-free face above a wrinkly, haggard neck, which experts said could prove he had had some kind of cosmetic treatment. He was in Los Angeles with his wife to celebrate his father Kirk's 90th birthday.

To kick off the celebration Douglas senior issued a statement urging young people to try and make a difference to the world they live in.

The star of such epics as Spartacus, Paths of Glory and Lonely Are The Brave wrote: "My name is Kirk Douglas. You may know me. If you don't - Google me.

"I was a movie star and I'm Michael Douglas' dad, Catherine Zeta Jones' father-in-law, and the grandparents of their two children. Today I celebrate my 90th birthday."