Bear Grylls is serious about his diet.

In a new interview with GQ, the “Running Wild: The Challenge” star opens up about his eating habits, including why he gave up veganism.

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Though previously a big proponent of veganism, Grylls says he’s now “super against nuts. And against grains, wheat, and vegetables. They affected my health negatively. I was a massive advocate of the vegan lifestyle for years, and wrote a book on it, but my health tanked on it.”

He continues, “When I got COVID a couple years ago, I doubled down on what I thought was healthy—raw juice, vegetables—and got mega-sore kidneys, almost kidney stones. The more research I’ve done, I’ve noticed raw vegetables are really not good for you. So I’ve started incorporating quality grass-fed steak and liver. My lunch is meat, eggs and dairy, a lot of butter, and fruit. I have liver probably every other day. I started to get strong again.”

Despite his new anti-vegetable stance, Grylls says he’s “not super strict,” explaining, “I changed my mind-set away from vegetables are great to realizing we’ve had millions of years of evolution where we’re designed to eat meat and milk and eggs. And fruit—sweet, bright colors—and a lot of honey. It’s made eating a lot more fun.”

He says, “I have combinations of eggs fried in butter, greek yogurt with honey and berries. Before I’d think, ‘Oh, I have to have a salad.’ It’s a revolution to me.”

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While out adventuring in the wilderness, Grylls has eaten some unusual foods, but he generally says away from that sort of eating when he’s at home.

“I’ve done so much over the years: Drinking blood from a buffalo artery, munching on raw liver and heart. It’s not difficult, but it’s not very pleasant,” he admits. “If I’m at home, I’m not going to be tucking into raw steak and liver. Food is a great pleasure, and it can be cooked so beautifully. I tend to have it rare, but I like it cooked, unless I’m in survivor mode.”

Asked what is the first food he likes to eat when getting back home from adventuring, Grylls says, “I’ll make a burger from grass-fed mince, with cheese and an egg on top, cooked in tallow, fry some white rice in it. A scoop of bone marrow, and a massive tub of Greek yogurt, and honey and berries. If I was to have a treat, I’d have some cocktails and a sourdough pizza. Maybe a good British roast, sticky toffee pudding. And freshly squeezed orange juice. I found eating like this, I have fewer cravings.”