At one point in the latest episode of the BBC programme, Theroux asks Joshua about his smoking habit as a teenager, with the 34-year-old revealing: “I fell in love with the fitness regime, because when I was a young lad I was on the ganja, the haze.
“If you can’t get these distractions out your life, you can’t put your full focus and attention on improving as an athlete. So for me, when I stopped smoking, I was able to progress.
“[I was smoking] maybe like six spliffs a day – wake and bake, baby. My mum’s not gonna be happy about this, right, but [I was] probably about 13 [when I started].
“[I would smoke before school] or would bunk off school. I can’t really... If you’re listening to me, kids, don’t do it! It’s not good.”
When asked whether smoking helped him at school, Joshua replies, “Not at all! I was in Reading jail in 2009, then in 2011 I [almost] got kicked off the Olympic team for carrying drugs.
“I really honour the Olympic committee, because I got kicked off the Olympic committee at the time, and I started smoking again.
“Sean [Murphy, from Finchley & District Amateur Boxing Club], called my mum and said: ‘Get your son back in the gym, stop messing about, he’s got talent.’ Then, about six months later to a year, Rob McCracken backed me. He stuck by me and said: ‘Let him on the squad, he’ll sort his life out. Trust me.’”
Much of the episode focuses on Joshua’s points win over Jermaine Franklin in April, when the Briton bounced back from two straight losses to Oleksandr Usyk. “AJ” has since fought again, knocking out Robert Helenius in August.
Louis Theroux Interviews: Anthony Joshua airs on BBC Two on Tuesday 7 November, starting at 9pm GMT.