Watch the stomach-churning moment boxing champion Joseph Parker rips the flesh of a freshly caught fish apart with his teeth

• Joseph Parker eats raw fish from a bucket
• Boxers say it's a great source of protein
• Some martial arts fans are put off by the graphic footage

New Zealand boxing star Joseph Parker has shocked fans with a stomach-churning video of him crunching a freshly caught fish with his teeth.

Parker, 32, has turned his career around in recent years, defeating top-tier opponents such as Deontay Wilder and Zhang Zilei.

The former champion attributes his comeback in part to rigorous training and a disciplined diet, but combat sports fans were surprised by a video he recently posted to social media.

The footage shows Parker sitting on a dock in front of a bloody bucket, using his teeth to tear apart a freshly caught fish.

Parker tore the animal apart with his mouth, then dipped it into the bucket and ate some.

“This guy is not doing well,” one fan commented.

“He'll get sick eventually,” replied another.

“Fine,” posted a third.

Parker, who is of Polynesian descent, later explained that eating raw fish is a healthy habit and that tearing fish apart with one's teeth was “something we used to do” in the past.

“I do it every day,” he said in an interview with former Australian-Samoan world champion Jai Opetaia.

“Protein. If you want proper protein…you want fresh!”

A traditional Samoan dish called “oka” involves raw fish, but Opetaia wasn't too confident about Parker's cooking technique.

“It's called oka,” Opetaia said. “It's raw fish cooked.”

“I don't know what it's like to catch a fish from the ocean.”

Parker works with nutritionist George Lockhart and adopts a strict diet focused on fruits, vegetables and lean meats.

Parker's favourite food is raw fish, and Lockhart is amazed at how much the New Zealander can eat.

“We have Sunday off, but we have a busy practice on Monday so we'll work towards that,” Lockhart said during Parker's training camp in Ireland.

“I'm going to this sushi restaurant. [in Dublin] He eats around 40 pieces of sushi a day and there are even pictures of him carrying a giant ship!

“Every time we go there, people say, 'That's enough for four,' but Joe eats it in a flash!”