The blonde beauty admitted the group were under a lot of pressure to look a certain way and the stress she was under only made her skin flare-ups worse.
Asked if she felt any pressure about her appearance, she told New! magazine: “Massively, massively.
“I had horrible cystic acne when I first became a Doll and it almost cost me my place in the group.
“The pressure to get rid of it was intense, but it also caused more stress, which made me break out.
“As a dancer, finding a good relationship with fitness and food became key.”
But these days, Kimberly is less concerned about how she looks and her exercise regimes are all about building stamina and staying strong and flexible.
She said: “I’ve had to fight my battles with the way that I look but now, instead of focusing on my waistline and my six-pack abs, it’s more about what my body can do.
“I want to be able to get on stage and be the best Pussycat Doll. I want to have stamina and flexibility.”
The 38-year-old star – who has children Willow, six, Maple, three, and Ford, 15 months, with husband Max Rogers – insisted she and the rest of the band didn’t get competitive over how they looked but were a great source of support for one another.
She added: “We were supportive of each other. We were each other’s workout buddies but also there to be a shoulder to cry on when being in a girl band becomes too much.
“We had this pressure to be the winning girl band and were up against women with incredible bodies.
"We were fortunate that the amount of fitness involved with our shows kept us in good shape.
“That’s not to say we didn’t feel the pressure in between and it was very vocal that we had to look a certain way.”
