Kesha "went through a horrible filler phase".
The 39-year-old pop star admits that she's always been sensitive to online comments, and that "people have commented on [her] body" since the start of her career.
She told the Call Her Daddy podcast: "I internalise those comments, I make that the word of God, I try to adjust my body to somebody else's ... what they want me to be."
Kesha said the pressure to conform to society's beauty standards led her to experiment with filler. However, it's something that she now regrets doing.
The singer - who released her debut album, Animal, in 2010 - said: "God, that sucked. Because I was like, 'Oh, that's what I should do.' And then I'm like, 'I actually don't like the way that looks.'"
Kesha also acknowledged that it's tricky being a woman in the spotlight.
She said: "It's this constant dance with society on what it does mean to be a woman and what is acceptable and also, we're not supposed to age. Trust me, I don't want to. But like, I don't know what else to do."
Meanwhile, Kesha previously admitted that she found her sudden rise to stardom to be "terrifying".
The pop star enjoyed her first major success in 2009, when she featured on Flo Rida's hit single Right Round, and Kesha later admitted that she struggled to adjust to her new reality.
The Tik ToK hitmaker told People: "I went from being someone that sleeps in a sleeping bag at a punk house half of her life — everyone called it the Drunk Tank — and then a year and a half later I’m opening for Rihanna.
"It was terrifying, but it was so fun."
Kesha's family didn't have much money during her younger years, but she always found inspiration and hope in music.
The pop singer said: "When I was little, we were on food stamps. I remember thinking, ‘What makes people really happy when they’re having a hard time? Happy songs do that.’"
