The pop icon opens up exclusively to PEOPLE about her decision to partner with anti-wrinkle injection, Xeomin

Christina Aguilera has been owning her image since she first stepped onto the scene as a child star at the age of 6. And to hear her tell it, she was never going to let anyone dictate how to feel about her appearance. She even wrote a Grammy-winning anthem about self-acceptance — 2002’s Grammy-winning chart-topper, “Beautiful.”

Now, more than 20 years later, the 42-year-old superstar is continuing to stay authentic to herself while exploring products that make her look and feel her best. In an interview with PEOPLE, Aguilera gets candid about her first-ever injectables collaboration with Xeomin, an anti-wrinkle injection used to improve the look of frown lines, stepping in as a brand partner for its empowering ‘Beauty on Your Terms’ campaign. (Gwyneth Paltrow has previously teamed with the brand.)

“I’m always interested in finding new products that excite me and make me feel my best,” Aguilera tells PEOPLE. “Xeomin felt like the safest way to go because it doesn’t have any extra ingredients. It’s reassurance that no matter how tired I may be, I have back-up.”

Aguilera’s foray into the “smart tox” space has not only given her added confidence, but helped her maintain a more “natural look,” something that’s top of mind for her as a singer and performer.

“We like expression, especially in my line of work,” she says. “I don’t want to have a frozen face. Whether it’s being on-camera or performing onstage, I have to stay authentic to my emotion.”

And while Aguilera is open to trying new things to make her feel her most confident, she also hopes to flip the script on the language used around aging.

“Viewing aging as a negative is a super old-school approach,” Aguilera tells PEOPLE. “I’ve seen myself go through different stages of my life and complain about certain things. As I’ve gotten older, I look back, and I’m like, ‘God, every stage is a new era.’ I’m really into feeling more self-assured as you get older. That’s the thing to truly embrace. It’s harmful when [aging] becomes an obsession.”

She adds: “I also think that everybody has a different outlook with how they want to age. It’s a very personal conversation — what works for some people might not work for others.”

According to the superstar singer, more than two decades in the industry has taught her to embrace the evolution of her appearance and womanhood.

“Things are going to change as you grow older—especially as women. I started performing at around 6 in my hometown, and I never stopped,” she says. “Being in the public eye is an added element that can complicate your view of yourself. People are going to have an opinion no matter what you do, no matter what you wear. The artistry always comes first to me.”