Secrets behind Wayne Rooney's astonishing World Cup 'glow up': KATIE HIND reveals what's behind his slimmer physique, thicker hair and fresher complexion...

Glitz and glamour have arguably been in short supply inside the 's World Cup studio during this year's tournament.

Bosses elected not to send its star presenters to the US to host its coverage, and the green screens and pot plants that have stood in for locations such as Miami or Dallas – beamed to millions from a distinctly more mundane Salford – have left television audiences a little uninspired.

But even so, a rather unlikely pundit has attracted attention for bringing a dash of much-needed pizzazz.

And no – it's not a glamorous new female anchor, but former England captain .

Now the BBC's most famous pundit, 40-year-old Wayne – who has himself joked about being unkindly compared to the animated ogre Shrek – has undergone an astonishing glow-up.

Gone is the tubby build, beard and receding hairline; and in its place is a slimmer physique, a noticeably thicker mane, a fresher, clean-shaven complexion and a stylish designer wardrobe.

The transformation has not gone unnoticed on social media.

'Just seen Wayne Rooney!' one wrote. 'I tell you what, he's lost a lot of weight and looks so much better!'

Another added: 'I am seeing Wayne Rooney on BBC and he is looking great. So happy to see he is looking after himself.'

One even joked that his wife, Coleen, 'must have put him on a diet'.

Audiences have speculated over how he has achieved his new look, questioning whether he had resorted to weight-loss jabs.

But I can reveal that Wayne's overhaul is the result of the trendy Macro diet, which involves individuals tracking their daily intake of the three 'macronutrients': carbohydrates, fats and proteins.

How much each person can have in a day is calculated based on their height, weight, activity level and weight loss goals. But it can help people lose weight, build muscle mass, manage their blood sugar levels and improve health more generally.

And while dieters can eat any type of food as long as it fits into their calculations, typical foods on the diet include lean beef, salmon, Greek yogurt, whole grains and pumpkin seeds.

It is quite the turnaround for the former Manchester United star, who was known for gorging on pizza and McDonalds before Premier League matches – a habit which often got him into trouble with his managers.

And rather than Coleen, 40, stepping in to help him with his wardrobe, I'm told it was Wayne himself who decided to give his style an overhaul. I understand he has even consulted a stylist over what he should wear on television.

With their help, he has picked out carefully fitted shirts, tailored jackets and slimming knitwear – with a particular fondness for high-end menswear brand Hugo Boss.

'Wayne is not a fashionista like his wife,' says a source familiar with him. 'He grew up wearing tracksuits and still loves to wear them today but that isn't possible on television. So with a little bit of help he has spruced his clothes up.

'He even has a new-found love for fashion, and he was even teased by Gabby Logan recently when he commented on how much he loved US manager Mauricio Pochettino's clothes and wanted to know where he had got them from.'

Meanwhile, there are whispers that Wayne may have undergone another hair transplant to cultivate a more youthful look. He has been open about undergoing such procedures in the past, admitting that he had two 'follicular unit extractions' on London's Harley Street in 2011 and 2013, at an estimated cost of £30,000.

'Wayne has always been self-deprecating about his hair, he didn't have much even when he was a teenager,' says a source. 'Who could blame him for doing it again, if he indeed has?

'He looks great, and there is much more of it now. It looks thicker and sharper than it ever has before.'

His Achilles heel, however, has always been alcohol. Wayne has found himself in trouble over the years for his drinking habits, and has even conceded that he would be dead if Coleen had not been around to support him.

In a heart-wrenching admission last year, Wayne told how he 'just drank for two days straight', would play a match and score a couple of goals, and then continue to 'drink for another two days straight'. Coleen, he added, had been his saviour.