The Greatest Showman actor was initially inspired by his Down to Earth co-host Darin Olien to take up a vegan lifestyle.
While he's previously championed the benefits of living a plant-based life, Zac has since switched back to eating meat.
Explaining his lifestyle change to Men's Health, the actor said that while 'morally, of course, I still wish I was vegan,' his body just can't hack it anymore.
Zac explained that while he wholeheartedly believes in veganism, his 'body wasn't processing vegetables in the right way' so he opted for a new diet, saying that now isn't 'the time or the place to put pressure on yourself.'
Zac's new diet features intermittent fasting, two meals a day, and 'clean' meats - by clean he means chicken or elk.
"I decided to stop it and try something new. Intermittent fasting has been really helpful with that.
"I started intermittent fasting just after I stopped being vegan," the actor explained.
His fast normally breaks at around 11:00am, with the actor opting for chicken broth soups and veggies, for his second meal of the day he goes for a clean meat and 'a healthy carbohydrate like sweet potatoes or quinoa'.
The whole idea, Zac says, is to get 'enough nutrition to, sort of, sustain me throughout the day.'
Still, that's not all that Zac is eating, because he's also partial to a less popular type of meat: "This is kind of weird, but I really like organ meats. I love liver and onions."
While Zac says his diet varies depending on what role he's starring in at that particular time (he was pretty much in ketosis the whole way through Baywatch), he explained: "I give myself permission to, sort of, let up and eat what I need to eat, if I'm craving something, I'll just have it. It's not the time or the place to put pressure on yourself unless you really need to be shirtless that entire film."
So, there you have it, Zac's no longer vegan, but morally he wants to be.
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