"My own health, and after all the information I gathered about the mistreatment of animals, I couldn't continue to eat meat. The more I was aware of, the harder and harder it was to do," the 28-year-old said.
It was his Hunger Games co-star Woody Harrelson who convinced him to take the plant-based plunge.
"I have a lot of friends who are vegan. Woody Harrelson was actually one of the original reasons I became vegan, because he's been vegan for, I don't know, 30 years or something. So, with the facts I was gathering, and then just how I was physically feeling, I felt like I had to do something different, so I adopted this vegan-diet lifestyle. It's been almost five months now," he said.
"There are no negatives to eating like this,” he continued. “I feel nothing but positive, mentally and physically. I love it. I feel like it also has a kind of a domino effect on the rest of my life."
He said he’s also convinced his eldest brother, Chris Hemsworth, to change his eating habits.
"Chris is obviously extremely healthy and has played Thor and has had to work out a lot over the past few years," Liam explained. "But he has a lot of digestive issues, and he's constantly trying to figure out what's best for his system. Through talking to me, he's somewhat adapting, I think, to eating more vegetables and more plant-based stuff."
His fiancé, Miley Cyrus, is also a huge fan of the vegan lifestyle, so much so that she got a tattoo to symbolise her commitment to it.
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