The singer — known to fans as the iconic Sporty Spice — first met King Charles III (who assumed the title of King upon his mother Queen Elizabeth II’s death on Sept. 8) with bandmates Geri Halliwell, Emma Bunton, Melanie “Mel B” Brown and Victoria Beckham at a U.K. gala celebrating the 21st anniversary of the Prince’s Trust in 1997, when he was still known as the Prince of Wales.
In true Spice Girls fashion, they ignored all royal protocol, with Halliwell Horner and Brown planting heavily lipsticked kisses on King Charles’ cheeks. Halliwell Horner also gave him a pat on his butt.
“At the time, I was one of the shyer members of the band, so I was cringing inside as the girls were kissing Prince Charles,” Chisholm tells PEOPLE over a Zoom call from London. “I was like, ‘Oh my gosh, I can’t believe they’re doing it.’ But now I’m really proud that the girls did that because I think that’s part of the reason the world fell in love with the Spice Girls. We were kind of doing what everybody wished they could do, and it was never with malice. It was always with a smile.”
“Now that Charles is our King, it kind of makes it even more naughty,” she adds with a laugh. “Those naughty Spice Girls!”
The memory is just one of the many Chisholm shares from her time in the band in her forthcoming new memoir THE SPORTY ONE: My Life as a Spice Girl, set for release on Sept. 27.
Alongside the fun times, Chisholm also goes into detail in the book about her more difficult chapters, including her private struggles with anorexia and depression at the height of the band’s popularity.
“I really want people to see behind the closed doors of what went on with the Spice Girls through those crazy years and beyond,” she says. “The book is quite balanced in the light and the shade, which is life.”
Raised in the small industrial English town of Widnes by mom Joan, a singer, and dad Alan, a travel agent, Chisholm grew up singing and always knew she’d be a performer. But when the Spice Girls rose to fame with their smash single “Wannabe” in 1996, when she was just 22, she wasn’t prepared for life under the microscope.
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To cope with the constant criticism of her appearance in those days, she started to cut back on food and exercise excessively. But it wasn’t only other people’s opinions of her that fueled her eating disorder — it was also her “internal dialogue,” she says.
“We’re so cruel to ourselves,” she says. “We speak to ourselves in a way we’d never speak to another human being, let alone somebody we love. When I look back, I feel so proud of everything that we achieved, but it is tinged with sadness because I just think if I hadn’t been feeling those things, I could have enjoyed it so much more.”
While Chisholm says it was “amazing” shooting the Spice World movie in 1998, she writes in her memoir that she was struggling at the time and at her thinnest.
“How I look in that movie is very difficult for me to see,” says Chisholm, who took 16 years to watch the film again after its premiere. “I think that’s why I avoided it for so long. I was very thin at that point and and for a long time, that was hard to watch.”
In 1999, a year prior to the Spice Girls going on hiatus, Chisholm embarked on a solo career with the release of her debut album Northern Star. Meanwhile, her eating disorder evolved from anorexia to binge eating.
In the early 2000s, things got so bad that she struggled to get out of bed while on a trip to Los Angeles with her family.
“The most difficult years were 2000 and 2001,” she says. “This is when I was diagnosed with depression and started to really address my eating disorders. I hadn’t had a healthy lifestyle or attitude for a few years, and that got me into a really unhealthy place.”
After being diagnosed with depression, Chisholm began to manage her mental health with talk therapy and medication. Over time, her issues with disordered eating began to ease too.
She also credits her 13-year-old daughter Scarlet (with ex-husband Thomas Starr) for keeping her on track.
“For me, it was like the responsibility of having a daughter enabled me to take more responsibility for myself,” she says. “She’s very much my teacher, but then I realized I’m forming this incredible person in front of me. That responsibility gave me a bit of a kick up the bum to just go, ‘Hang on a minute. You’ve got to treat yourself better.'”
Though revisiting those hard points was difficult for Chisholm, she thought it was “important” for the book.
“I knew I had to do it, and I knew I had to do it in a very honest way because I wanted it to be beneficial to other people,” she says. “I’m not just telling my story. I want it to go to some good use.”
Another lesson Chisholm hopes people take away from reading her book? Trust your gut.
In her memoir, Chisholm reveals that she was sexually assaulted by a massage therapist at a spa in the Istanbul, Turkey, hotel she and her fellow Spice Girls were staying in prior to their first performance as a band in 1997. When she called the reception desk to explain what happened afterwards, they said the masseuse had already left.
“I was like, ‘Is it just me? Am I wrong?’ because I felt like I was so inexperienced in that environment,” she says. “I didn’t know what the rules were, what the etiquette was, and I felt uncomfortable. Since it was the night before the first big Spice Girl show in Istanbul, I had to just get on with other things. My biggest regret is that the person that did that to me wasn’t held accountable.”
“I think it’s just really, really important to know that if something doesn’t feel right, then it’s not right,” she adds. “It’s incredible how silenced women have been for such a long time. Men need to be held accountable.”
After all she’s weathered, Chisholm says she feels “really proud” to still be standing.
“Achieving the things I did while dealing with the things I did, I feel, has made me a warrior in this life,” she says. “You never know what life’s going to throw at you next. But I know I have this inner strength.”
As she looks to the future, she’s hoping to get back on stage with the Spice Girls — who last toured in 2019 — soon.
“We need to make this happen,” she says. “We’re constantly talking, and I’m trying to figure out when it works best for everybody with kids, other careers and different things going on. We just have to make the time frame work for everybody.”
With her 50th birthday also coming up in 2024, Chisholm — who split from longtime boyfriend Joe Marshall during the COVID-19 pandemic and says dating is on the “back burner” for now — feels like this is the start of a next, beautiful chapter.
“I feel like I’ve kind of closed a chapter of my life, and I’m really excited about the new one coming, which includes the big 5-0,” she says. “I think as you get older, you realize more and more how precious life is, so you must fill it with the things that give you joy. So for me, that is being a mom, being an artist, and getting out there and connecting with people. Who knows what the future holds?”