The Voice judge, 34, told followers that with her "it's all real, all the time," adding that she "felt like it was time to start sharing some personal stuff with you guys."
The former teen pop star has a long history of earning an A-plus in confidence; just take a look at her five fiercest moments in body positivity.
When She Posed Nude and Pregnant on the Cover of Marie Claire
Aguilera quite literally bared it all for a 2007 issue of the mag, posing nude while pregnant with her first child, son Max Liron, now 7. In the cover story, the singer was candid about everything from trying to conceive to pregnancy hormones, and also opened up about the pressures of expressing her sexuality in the spotlight.
"We're so labeled. If you're too sexual, you're slutty. If you're not sexual enough, you're a prude," she lamented. "I have more than one side of me that likes to get out on a stage and sing. Sometimes I want to be aggressive, sometimes I want to feel empowered in my sexuality and my vulnerability. I want to put all that out there."
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When She Admitted She Once Felt 'Too Skinny'
"I lost so much weight that I was too skinny," Aguilera told Marie Claire about altering her curvy physique for her role in the 2010 film Burlesque. It takes a supremely confident person to be so open about being unsatisfied with their body, but the "Dirrty" singer doesn't waste too much time worrying about tipping the scales one way or the other. "If I have to choose between working out and spending time with my son after a hard day, it's not even a question," she added to Redbook in 2013.
When She Shrugged Off the Criticism
Being in the spotlight since the age of 17, Aguilera has "been on all sides of the spectrum" when it comes to taking body criticism. In 2012, she talked about dealing with comments about her image at a TCA panel for The Voice: "You can never be too much of anything. You can never be too perfect, too thin, too curvy, too voluptuous, this, that … [Every] female in this business at one time or another has had criticism." But the former teen queen has perfected the art of ignoring the "massive scrutiny," adding, "As long as I'm happy in my own skin, that's all I need, that's all the confirmation I need. I'm happy where I am, I have a boyfriend that loves my body, I love my body, my son is healthy and happy. That's all that matters."
When She Sang 'Beautiful'
Who can forget Aguilera's 2002 body positive anthem? With lyrics like "You are beautiful no matter what they say/Words can't bring you down," she gave everyone who has ever felt insecure a reason to celebrate their unique flawlessness. In the song's video, Aguilera wasn't afraid to showcase her own feelings of self-consciousness at the same time, and she highlighted the many different iterations of body image issues.
When She Was Candid About Her Sex Life – and Felt 'Sexier Than Ever'
Aguilera is not shy about her enthusiasm for between-the-sheets excitement. When she graced Maxim's cover in 2013, she really opened up about her healthy drive for intimacy: "Sometimes being sexual with my partner is a great way to blow off steam at the end of a hard day's work. I'm not the girl who's going to be too tired," the singer said. "I think every woman should relax and allow herself to be pleased in the bedroom … I'm 32 and I feel sexier than ever because you know what you want."