Television presenter Gregg has featured as an almost permanent fixture on our screens since he first hosted Saturday Morning in 2002.
Despite being best known for his role as culinary judge on much-loved cooking competition series MasterChef, the 57-year-old greengrocer has also been investigating the UK's biggest food production units on BBC Two's Inside The Factory alongside Cherry Healey and Ruth Goodman since 2015.
Now, after almost 20 years in the media spotlight, Wallace has featured in recent headlines for his extreme lifestyle change, as well as his tumultuous relationship history.
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But what do we really know about the man who once referred to himself as "the fat, bald bloke on MasterChef who likes pudding"?
Early life and television career
Born in Peckham, South London, a 15-year-old Wallace left school to delve into the world of groceries. He began work as a warehouseman at Covent Garden Fruit and Veg Market before going into sales. After being told he should start his own food corporation, he opened George Allan's Greengrocers, which built up an eventual turnover of £7.5 million.
Wallace quickly gained recognition for his knowledge of fruit and vegetables, later being invited to co-present his own BBC radio 4 show Veg Talk alongside Charlie Hicks.
2002 marked a crucial point in Wallace's career, as he landed his first on-screen role as host of weekend cookery show Saturday Kitchen, and despite being replaced by Antony Worrall Thompson just a year later, he soon became co-presenter and judge of much-loved BBC series MasterChef alongside Aussie chef John Torode, where he was rapidly recognised for his dramatic presenting style, shouted delivery and impassioned facial expressions.
Since 2008, the former grocer has appeared on popular food documentaries, investigating the public's attitudes towards food, such as The Money Programme, Supermarket Secrets and Eat Well for Less? Wallace has also travelled across the world broadcasting factual shows about the food industry, whilst also making various guest appearances on popular entertainment programs such as Strictly, The Chase and Who Do You Think You Are?
Weight loss and extreme body transformation
In 2013, the culinary legend was shockingly informed by healthcare professionals that his life would be at risk if he didn't change his lifestyle and attitude towards food. He recently disclosed to Good Morning Britain hosts Susanna Reid and Richard Bacon that the 'wake up call' to lose weight was seeing himself get "bigger and bigger" on the TV screen.
"I was overweight," he told ITV viewers. "I was eating all the wrong things. I was boozing quite a bit. I had a good doctor that I had a good relationship with and he said, 'Look, let's do a blood test and stuff', and he phoned me up and he said, 'Your cholesterol is actually through the roof'. He said, 'If we don't change, you're going to be seriously ill. You're heading for a heart attack'."
A standard cholesterol test in the UK measures the level of total cholesterol in your blood, made up of both "good" and "bad" cholesterol. The healthy amount that a person should exhibit is 5 or below. Gregg claims his own cholesterol has approached 14.
Now, he has transformed into a fitness guru, having dropped a mind-blowing 4.5 stone since 2017 and is now encouraging the public to make healthier food choices this year.
He explained, "What I did, was I taught myself about healthy eating. I realised what I could eat a lot of, and I realised what I had to cut down on. I eat three big healthy meals a day and I mean that - meals that actually fill me up so that I'm not hungry, so that I don't want to snack. I cut down the takeaways, I reduced the booze, but I've never, ever been on a diet."
Since embarking on his fitness journey, the TV star has posted images of his extreme body transformation across his various social media channels, demonstrating his regular progress. He also recently set up an entirely online fitness regime, 'ShowMe.Fit', which contains fitness guidance and workout routines and nutritional advice.
Relationship history
As well as well-being and health advice, Gregg's website also includes numerous healthy cooking recipes, handcrafed by his wife, Anne-Marie Sterpini, whom he has been married to since 2016.
The pair met online after the 35-year-old caterer tweeted the TV chef to ask if rhubarb went well with duck when cooking. In 2015, Wallace told Hello, "I just looked at Anna's photo and thought, 'Wow, she's pretty'. So yes, rhubarb, which was considered an aphrodisiac in medieval times, brought us together."
Sterpini, who is 21 years younger than Wallace is his fourth wife and they share a son, Sid, born in May 2019.
At age 24, whilst working as a greengrocer, Wallace married his first wife Christine in an impromptu ceremony, which they commemorated with a meal in a pie and mash shop nearby, however just six weeks later, the pair split. In his autobiography, Gregg jested that the marriage was "possibly the shortest marriage in the world" and claimed to have known it was a mistake before it had even happened.
In 1993, he met his second wife, pastry chef Denise, with whom he welcomed a son, Tom, the following year. Four years later, Denise gave birth to their daughter, Libby, and the pair finally tied the knot in 1999. Despite being married for five years, they later divorced in 2004 when Denise discovered the MasterChef star was having an affair with one of his employees.
Wallace also met his third wife, biology teacher Heidi Brown, on Twitter. The pair briefly exchanged messages on the networking site, however their relationship moved quicker than expected. Just four months later, they decided to live together, eventually getting married the following year. Their relationship would be short-lived however, with the 'lovebirds' separating just 15 months later.
He and his current wife, Anne-Marie became engaged in December 2014, later marrying at Hever Castle in Kent in August 2016 with his MasterChef co-host/judge John Torode was his best man.
Inside The Factory continues on Wednesday, February 2 on BBC Two at 9:00pm.
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