The chef wowed fans when he showed off his new slimline look on Instagram in 2019 after losing over four stone, and later shared that his doctor had warned him he was on his way to a heart attack if he didn't do something.
He has now told The Sun that his appearance was a big factor when he started his body transformation.
"My motivation at the start was, ‘I just want to look better on the telly’," he said.
“But now it’s, ‘How fit can I actually get? Can I actually have the body of a 20-year-old at 60?’"
Wallace, 57, slimmed down by changing his diet, exercising and cutting back on drinking.
He said he's very proud of what he looks like now, particularly at his age, and won't hold back when it comes to flaunting his topless body on social media.
“I feel more attractive, I’m nicer to be around and, let’s be honest, my wife is 22 years younger than me and while I can’t change my age, at least I can change what I look like," he said.
Wallace tied the knot with his fourth wife Anne-Marie Sterpini, 36, in 2016 and they welcomed a son together in 2019.
In 2020 he said that he didn’t want his younger wife to have a “fat old husband”.
He told Closer magazine at the time: "Having my baby boy made me want to be fit and strong. I can now go for long walks, which I wouldn't have been able to do before.
“Anne being younger than me was even more of an inspiration to be fit – you can have an old husband but she didn't have to have a fat, old husband.”
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