Celebrity SAS: Who Dares Wins star Jack Joseph has opened up about a devastating decision that nearly cost him his life.

Celebrity SAS: Who Dares Wins is back on screens with a new series (Image: Pete Dadds/Channel 4)

Celebrity SAS: Who Dares Wins star Jack Joseph has revealed a harrowing health ordeal that saw his parents monitoring him “every single hour” amid fears he might not survive the night.

The 25-year-old social media influencer is among 14 well-known personalities featuring in the Channel 4 reality programme, which puts celebrities through gruelling SAS training under the guidance of Billy Billingham MBE, Jason Fox, Rudy Reyes and Chris Oliver.

This year’s series – comprising eight hour-long episodes – pits British celebrities against their Australian counterparts, with former Love Island stars Dani Dyer and Gabby Allen, social media figure Cole Anderson-James and MAFS Australia’s Jessika Power in the line-up, reports the Mirror.

During tonight’s opening episode (January 4), Jack revealed a frightening health episode that spurred him to join the programme. The star, whose family has a strong passion for fitness, explained he took a legal steroid which had catastrophic consequences for his body when he was merely 19 years old.

“I went to a bodybuilding gym and I hear a lot of talk of this supplement which is like a legal steroid so I bought this supplement from a website and after six weeks I had liver failure. I went all yellow, pupils all yellow, my brain completely went south. It’s a hard thing to describe,” he disclosed on the programme.

Jack revealed he took a steroid that nearly cost him his life (Image: Channel 4)

“I had to go into hospital every day for about nine or 10 months to give blood everyday and I had to be under supervision. So the way you pass away with liver failure is, I was told, that you just go to bed at night and you don’t wake up.”

He recalled: “It was hard because every night, every single hour, my parents came in my room to check if I was dead, basically. That broke my heart.

“It’s hard to see your parents with that kind of emotional weight when you know you’ve caused it. Since then I’m quite an anxious person and that’s why I came on this course. I hide my emotions a lot.”

He has made a name for himself as a content creator (Image: Jack Joseph/YouTube)

Channel 4’s summary for the series states: “The celebrities will have no entourage, agents, filters or social media followers to rescue them. Instead, they’ll face sweat, physical endurance, sand, tears and the truth they’ve been avoiding – all in the blistering North African heat.

“The DS don’t care how famous the recruits are, how many social media followers they have or what they have done before this. As soon as they enter the selection process, their celebrity status and luxuries are stripped away and there will be no room for mistakes.”