Melanie Chisholm, the former Spice Girl Mel C, dates her past struggle with eating disorders and depression back to an incident at a Brit awards ceremony, she reveals on Desert Island Discs on 23 February.

In 1996, before the girl group was officially launched, Chisholm was almost chucked out of the Spice Girls for unruly behaviour, following “a scuffle between me and Victoria” that she has only recently admitted to.

“I am putting this all together in my head now and I think that is where the start of a lot of my problems was,” she tells Lauren Laverne, host of the BBC Radio 4 show.

“I had to be so strict with myself after that, in case I messed it up. What made it so devastating was how important I realised it was to me,” Chisholm explains. “We were at the Brits and we all had a few bevvies. I was told if it happened again I would be out.”

Such an early ultimatum from the band’s management, however, threw her into a damaging pattern of behaviour that eventually led to anorexia, binge eating and a diagnosis of depression in 2000.

The Liverpudlian singer, 46, who chooses to take Dusty Springfield’s biography Dancing with Demons to read on the fictional desert island, also admits that she is still hoping to represent Britain one day as a triathlete. Although always fit, Chisholm tells Laverne that she found her old persona as Sporty Spice difficult to handle in the early days of her fame, performing alongside Geri Halliwell, Victoria Beckham, Melanie Brown and Emma Bunton.

I was described as the plain one at the back. So I tried to make myself perfect. I ended up making myself really ill Melanie Chisholm

“I read about myself and wondered who that person was. I am sporty and athletic, but I am quite soft and gentle really,” she says. “I was described as the plain one at the back. So I tried to make myself perfect. I ended up making myself really ill. I was anorexic for a few years. I was exercising obsessively and I ended up being incredibly depressed. I was in denial.” Selecting tracks by Blur, Stevie Wonder and Billie Eilish for her island stay, Chisholm also refers to the bullying she once faced in the band, assumed now to have been at the hands of Brown. She did not speak out at the time, she says, because “when your fairytale happens to you, you feel guilty about complaining”.

The singer also said she had been ashamed of her depression and in denial until her GP diagnosed her illness and a lengthy recovery period began. “I went from being anorexic to having a binge-eating disorder. No matter how much you eat, you can’t fill this hole. My appearance began to change, which was the biggest fear,” she recalls.

During troubled moments in the Spice Girls’ short time together as a band she felt she was “always the diplomat”, adding: “I like a quiet life. I learned to keep my head down and stay out of the firing line.”

Halliwell’s decision to leave was a shock, she recalls: “We were devastated. It was really difficult and in all honesty the beginning of the end.”

The band did not officially split up, according to Chisholm, but by the end they were each recording their voice tracks separately.

The singer, who has since had solo success and appeared to acclaim in musical theatre, feels she has now learned to speak up for herself. “I have spent too long being quiet,” she says.

But reunion shows with the band that brought her fame are still a reminder of the force of girl power: “When we are on stage together we are formidable and we would kill for each other.”