He lost an impressive 20lbs after overhauling his lifestyle and adopting a vegan lifestyle in order to remain healthy enough to keep up with his son Eric, seven.
And Simon Cowell, 61, continued to show off his slender frame on Monday, when he stepped out for a stroll in London with partner Lauren Silverman, 43, and their son.
The music mogul, who last year broke his back, looked casually cool for the outing, sporting a black quilted coat with baggy blue jeans and a pair of boots.
Family stroll: Simon Cowell was seen stepping out for a stroll in London with his partner Lauren Silverman, 43, and their son Eric on Monday
Wearing a black protective face mask, he looked relaxed as he enjoyed his day out with Lauren, who looked typically glamorous in a smart taupe coat with skinny jeans.
Complementing her look with a navy top and beige Converse shoes, the American beauty accessorised with statement gold pendant necklaces and sparkling earrings.
Their adorable offspring Eric mirrored his dad’s style in a black padded coat, which he wore with jeans, grey running shoes and a colourful face mask.
He was flanked by his doting parents, who at points during the stroll were seen holding hands with the newly minted seven-year-old.
Casually cool: The music mogul, who last year broke his back, looked casually cool for the outing, sporting a black quilted coat with baggy blue jeans and a pair of boots
Glam: Wearing a black protective face mask, Simon looked relaxed as he enjoyed his day out with Lauren, who looked typically glamorous in a smart taupe coat with skinny jeans
They were also seen strolling together through London’s upscale Holland Park on Sunday, as they celebrated Eric’s big day.
Simon has shed more than 20Ibs in weight thanks to a fastidious vegan diet, which he changed in order to keep up with his son.
In August, Simon was rushed to hospital to undergo six hours of surgery after breaking his back in an electric bike accident at his Malibu home, forcing him to cancel all his planned TV work for the rest of the year.
The X Factor judge had been staying in LA while he recovered from his accident, but he was seen looking happy and healthy in Barbados for a family trip last month.
Healthy lifestyle: Simon’s fellow BGT judge Amanda Holden has previously said his weight loss is also the result of him switching to ‘skinny lager’ (pictured right in September 2018)
The accident occurred when the powerful machine ‘flew up in the air and did an accidental wheelie’ after he tried to change gears.
The music boss is thought to have been ‘surprised by the power’ of the bike and knew immediately that he ‘was in trouble’.
Following the accident, Simon tweeted: ‘Some good advice… If you buy an electric trail bike, read the manual before you ride it for the first time.’
He went on: ‘I have broken part of my back. Thank you to everyone for your kind messages.’
He then added in a second tweet: ‘And a massive thank you to all the nurses and doctors. Some of the nicest people I have ever met. Stay safe everyone Simon.’
Golden girl: Complementing her look with a navy top and beige Converse shoes, American beauty Lauren accessorised with statement gold pendant necklaces and sparkling earrings
Adorable: Their adorable offspring Eric mirrored his dad’s style in a black padded coat, which he wore with jeans, grey running shoes and a colourful face mask
His recent injuries and ongoing recovery saw him sit out of the resumed 2020 series of Britain’s Got Talent after it returned following England’s first lockdown.
In 2019 Simon said of his healthier lifestyle on The Ellen DeGeneres Show: ‘I went to see this doctor in London. We did some tests. And then a month later he said, “You have the worst diet I’ve ever met from any patient.”‘
Simon then added: ‘It’s like the Eric diet because he actually, apart from ice cream, he actually likes water. I mean, who likes water? And his raw vegetables. So I’m on like, the Eric Cowell diet.’
The TV judge’s new physique has impressed his celebrity pals, with his close friend and fellow Britain’s Got Talent judge David Walliams joking the star has become a ‘skinny b***h’.
Doting parents: He was flanked by his doting parents, who at points during the stroll were seen holding hands with the newly minted seven-year-old
Taking to Twitter to share his thoughts on Simon’s transformation, David tweeted a picture of his pal shirtless on the beach and said: ‘Skinny b***h,’ before following his post up with another of Simon that read: ‘Vegan diet my a**e.’
Amanda Holden, who also sits on the panel with Simon for Britain’s Got Talent, has also spoken out about his weight loss and claimed it was the result of Simon switching to ‘skinny lager’.
Speaking on Good Morning Britain to host Piers Morgan, she said: ‘He’s drinking lightweight beers, that’s the secret.
‘And I tasted it because I thought it was gonna taste, like, naff. Actually it’s quite decent. You could take a tip from him!’
Meanwhile, Simon also spoke about cutting down on alcohol last year, he told Extra: ‘I went to see this guy who’s very well-known. And he said to me, after doing some blood work, “You can’t have red meat, dairy, sugar, bread or gluten.”
‘I’m thinking, “What about alcohol?” And he said, “Maybe not quite as much as you had before.” And I did it and I stuck to it and it’s easy.’
Eric is Simon’s only child and he has credited his son for changing his life for the better, ever since he was born back in 2014.
Speaking on ITV’s Lorraine in September in 2019, Simon explained the impact Eric has had on him and said: ‘I see my life through his eyes now and it’s much more simple and it’s much more fun.
‘When you become a dad, something clicks in you. it’s all about them… You become very protective and importantly, part of the reason I changed everything in my life.’
Birthday boy: They were also seen strolling together through London’s upscale Holland Park on Sunday, as they celebrated Eric’s seventh birthday