JoJo's previous diet plan is one we won't be trying any time soon.
In an interview with Popsugar, the 25-year-old pop star reveals she used to inject herself with supplements in hopes of losing weight fast.
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"Here's something that I agreed to do that ended up messing with me psychologically," JoJo begins. "I was under a lot of pressure from a company that I was previously working with, and they wanted me to lose weight fast."
"So they got me with a nutritionist and had me, like, on all these supplements, and I was injecting myself -- this is a common thing that 'the girls' do by the way -- it makes your body only need certain calories, so I ate 500 calories a day," she continues. "This was the most unhealthy thing I'd ever done."
JoJo says it wasn't long before she gained all of the weight back, however, which made her feel "terrible" about herself.
"[At the time], I felt like, 'If I don't do this, my album won't come out,'" she reveals. "And it didn't! So it's not like it even worked! But I felt like I needed to do what I was told I needed to do, and I was 18 and really impressionable, but it really messed with me. It really hurt my feelings."
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Umm, we think it's safe to say this bizarre method just needs to "Leave (Get Out)" forever! Luckily, JoJo realized that too.
"I listen to other people's opinions. [But] listening and following are different things," she adds. "I think listening and showing respect to people you respect, it works for me. What you think about yourself and the decisions you make is what's most important."
For JoJo, those decisions are focused around music.
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It's been awhile since we've heard new jams from the singer, but she's back with a brand new album, Mad Love., her first full-length collection in ten years. (The album will officially be released on Friday, Oct. 14.)
On Thursday, the brunette beauty released her first single off the album, a track titled "F*** Apologies," which features rapper Wiz Khalifa. See the music video for the catchy track below.
Last September, JoJo marked her first official return to the music biz by debuting a sexy music video for "When Love Hurts."
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At the time, she told ET she wanted to give fans a "taste" of what was to come -- "an amazing album to follow, which I'm so proud of."
To hear more, watch the video below.