WWW- For aging Hollywood heartthrobs, little beats the indignity of a steadily receding hairline. As Mel Gibson, it seems, would testify.

The 50-year-old actor appears to have experienced a quite miraculous transformation in the trichological department.

And where, just a few years ago, the Braveheart star boasted a decidedly thinning mane – and two quite prominent bald side patches – today he is the proud owner of a veritable expanse of hair.

Instead of a greying, thinning crew cut of two years ago, the casually attired double Oscar winner was photographed with a thick, dark head of hair.

Grinning from ear to ear, as the star emerged from the hairdressers with his new hairstyle, there were rumours that he may have more than mother nature to thank for his new look.

Last night, Leonora Doclis from the Belgravia Trichological centre in London, said: “There is no way to be absolutely sure exactly what Mel has had done but it is certainly possible to get this kind of result with treatment.

“He has probably had either a hair transplant or a top-of-the-range hair piece put in. With a hairpiece – what in the olden days was known as a toupee – the best, most natural looking hair would be made up to give him thicker-looking hair.

“Individual grey hairs can be added to match up exactly with his own hair, giving him the natural salt and pepper look which he has here.

“This method needs maintaining every two to three weeks, but with someone of Mel Gibson’s stature and means, this is possible.

“The other alternative is a transplant. A unit transplant, costing up to £10,000, involves hair follicles being taken from the side of the head, where hair is naturally thickest, and inserted onto the thinning spots.

“Any scarring would be largely invisible. Whatever he has had done, Mel definitely looks the better for it.”

Of course, Gibson’s rapid hair growth may be down to nothing more than a trick of the light. But, if not, other methods of hair replacement include creams, gels and colour sprays.

With spray cans, specially made dyes are applied to bald spots, to ‘fill in’ the unsightly pink patch. Readily bought over-the-counter, they last only a few weeks.

Hair creams, containing the chemical beta catenin, are another option. When rubbed into the scalp the ‘miracle’ creams promise to reprogram hairless adult skin to grow new hair follicles. Male pattern hair loss is a combination of genetic factors and the influence of male hormones. As such, cosmetic products containing limited amounts of hair stimulating chemicals, are not guaranteed to work and scientists are still unable to discover a definitive cure for baldness.

While Gibson has not publicly admitted to having had a hair transplant, he would not be the first celebrity to undergo hair restoration treatment.

Usually the preserve of sportsmen, cricketers Shane Warne, Graham Gooch and rugby international, Austin Healey, have all endorsed hair replacement creams – much to the amusement of the rest of the sporting world.

Sir Elton John, who started going bald around twenty years ago, is perhaps the most famous hair transplant recipient. He underwent a series of procedures after becoming fed-up with wigs.