He wrote in the book: “To satisfy our insatiable appetite for meat we have developed very unnatural ways of breeding, keeping and killing animals. This far exceeds our nutritional needs for the health of myself and my family.”
Quite the U-turn
But the father-of-three has taken a big change of direction since then, and now completely avoids vegetables as part of his “ancestral way of living”.
“For a long time, I’d been eating so many vegetables thinking it was doing me good, but just never felt like it had given me any good nutrients compared to the nutrient density I get from basically blood or bone marrow – red meat,” he said.
“I’ve tried to listen to my body more, tried to listen to nature, and I don’t miss vegetables at all. I don’t go near them and I’ve never felt stronger, my skin’s never been better, and my gut’s never been better.”
And despite his once proud advocacy of veganism - he reportedly used to turn his nose up when his filming crew were eating sausages for lunch - Grylls says embracing red meat and organs has been the “biggest game-changer” for his health.
“I’ve found a counterculture way of living, of embracing red meat and organs – natural food just like our millennia of ancestors would have eaten for hundreds of thousands of years.
“And out of all the different things I do for my health, I think that’s probably been the biggest game-changer, in the sense of improving my vitality, wellbeing, strength, skin and gut.
“It’s just been getting away from the processed stuff and making the predominant thing in my diet red meat and liver and the natural stuff – fruit, honey, that sort of thing. It’s just about finding a more ancestral way of living,” he said.
And veganism is not the only diet trend Grylls has changed his mind about.
The 80/20 rule
Writing in GQ in 2016 to promote his Fuel for Life book, the TV personality revealed he was adhering to the “80/20 rule”.
“I eat healthily 80 per cent of the time, and that leaves me free to eat what I want for the remaining 20 per cent. And those cheat meals taste so much better when they are a treat rather than the norm,” he wrote.
But Grylls has now admitted that in hindsight it was not a healthy way of living, and left him “basically starving” for most of the time.
“I look back on that and think it’s such an unhealthy way to live – you’re basically starving for 80 per cent of the time and then you’re bingeing for the rest. That’s not good for the body.
“And I find now I’m always full when I’m eating so much meat and eggs and butter and fruit and honey – I’m never hungry. I go out and I’ll order three burgers and get rid of all the buns and the fries and just have the burgers. I don’t crave junk food,” he said.