Nick Knowles is aware he's not what many would picture when the word vegan comes to mind.

"You tend to think that most vegans are petite, small, slim people, and I'm not," states the 54-year-old TV presenter, best known for his 18 years fronting BBC One home-improvement stalwart DIY SOS. "I'm a 46-inch chest, 6ft 2in, 17-stone rugby player!"

But if Nick doesn't look like a typical vegan - that is, someone who doesn't consume any animal-produce, including dairy, eggs and honey, as well as meat - some members of the vegan community, ones at the more extreme end of the wedge, who he terms "funda-lentilists" - are at pains to point out he isn't really one anyway.

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Not your typical vegan

But that isn't to say that he hasn't tried. His lifestyle has been turned upside down since filming BBC Two's The Retreat last year, which saw him and a diverse group of participants head to a health centre in Thailand, ditching cigarettes, caffeine, alcohol and meat and replacing them with yoga, lots of vegetables and hikes through the mountains.

Nick lost nine kilos in three weeks, his cholesterol levels fell by a third, and his blood pressure dropped to a healthy level.

Since then, he has maintained a 'flexitarian' diet, meaning he largely eats vegetarian or vegan meals but will occasionally have meat or fish. It's a big change for a man who used to eat a sausage, bacon and egg roll on his way to work, snack on scotch eggs, and regularly go out for steak lunches.

And while his first cookbook, Proper Healthy Food: Hearty Vegan And Vegetarian Recipes For Meat Lovers, focuses on this huge shift, he's still upset the apple cart.

"If you could do one day a week as being veggie, congratulations, you should get a pat on the back," he reasons. "You've reduced your meat intake, that's fantastic. If you can do it two or three days a week, even better.

"If you could get to a point where you're meat-free during the week and only treat yourself to meat during the weekends... when I say something like that, the Vegan Society goes, 'What? Treat yourself to dead animals?'

"You're never going to encourage people if every time they fail, you batter them over the head. I've been saying more carrot less stick. Or you could say, more carrot less steak!"

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Don’t be deterred

And the father-of-four feels the message is too important to be deterred.

"The vegan community is watching this book very carefully and I'm slightly worried about what I'm saying, which is that it's OK not to be fully vegan, but I don't really care," he says, between sips of peppermint tea.

"I know the health benefits that come from eating a more plant-based diet are so important that we have to get past all of that rubbish, and encourage people to start eating meat-free once a week.

"A lot of guys are thinking, 'I don't want to go like my dad did and suddenly have a heart attack at the age of 46'. The dedication in the book says, 'To my family who stand by me, who ground me through my flights of fantasy and who want me to stay around a bit longer - the feeling is mutual', and that is what it's about."

Happier and healthier

Overhauling his approach to eating hasn't just benefited his physical health, either.

"I work with a lot of people who suffer very serious depression, so I'm not going to glibly suggest what I felt was medically diagnosed depression in any way, but undoubtedly the pressures of doing what I do and only getting home eight or nine nights a month because I'm on the road with work so much, brings all kinds of stresses and strains and worries. I might finish at 10pm in Newcastle, and the next day I'm filming at 8am in Brighton.

"I'm travelling through the night and getting two hours' sleep. I'm away from my young son. I don't see enough of my older children and it's been on public record that I've been having difficulties with my marriage," says Knowles, who separated from his second-wife Jessica early last year, though they've since reportedly revealed they're 'working on their relationship'.

"All of those things add layers of pressure on, and if you then add to it a life in the public eye, where everything's picked apart, there is a tendency to want to hide away. It brings certain anxieties, but I am very lucky I have a really good supportive family, and since I changed my diet, I'm undoubtedly happier and healthier."

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