Meghan Trainor Slams Backlash Over Her Weight Loss—And Reveals She 'Didn't Believe' Body-Positive Message In 'All About That Bass'

It may have been “all about that bass” in 2014, but in 2025, it’s apparently all about Meghan Trainor’s weight loss, or so the internet has decided.

Once again, Trainor has been shoved into Hollywood’s worst recurring storyline: unsolicited opinions about a woman’s body.

Fresh off revealing a noticeably slimmer figure—about 60 pounds down—the pop star has become the internet’s favorite new canvas for projection, speculation, and general collective nosiness. And like many public figures who’ve wandered into the crossfire of GLP-1 discourse, Trainor has decided she’s not taking the criticism quietly.

Earlier this week on Entertainment Tonight, Trainor smiled through what should have been a breezy “tell us about your new music!” segment, until it quickly swerved into weight-loss conspiracies and the kind of drive-by concern-trolling that only the internet can produce.

Meghan, for her part, came prepared:

“The world’s getting crazier and meaner, and they’re louder. I’m literally for the first time ever, after having babies, taking care of my health to the highest level, and I’ve never felt better, and I look incredible."

"I feel great, and that’s when people attack me? I was like, what?”

Internet logic, of course, says: if you feel good about yourself, we can’t allow that.

The 31-year-old mom to sons Riley, 4, and Barry, 2, with her husband and professional Spy Kids actor Daryl Sabara, noted that the negativity has grown louder, but her well-being isn’t up for debate.

She said:

“I’m taking care of myself. I have to find a way to not be affected by that.”

You can watch the interview clip here:

Trainor has long been transparent about her postpartum recovery, especially how tough things felt after her C-section with Riley. Back in 2022, she told E! News that she was “not feeling great,” which prompted her to overhaul her habits, including a gluten-free, dairy-free diet, strength training, and the kind of consistency that doesn’t lend itself to a viral “What I Eat in a Day” montage.

Trainor revealed:

“If I can survive a C-section, I can do anything! I was very dedicated, and I started seeing the pounds come off like one week at a time, one pound.”

But this year, she said the quiet part loud: yes, she used medication. Trainor shared that she and Sabara had been prescribed Mounjaro—the buzzy tirzepatide injection sweeping Hollywood faster than a Marvel reboot with a new multiverse.

And in true Gen-Z-adjacent fashion, she confirmed it on Instagram, prompting cheers, think-pieces, pearl-clutching, and at least one extended family group chat asking whether their insurance covers “that Ozempic thing.”

Trainor didn’t stop there. She’s opened up about cosmetic tweaks, too, admitting on her Workin’ On It podcast that Botox had sometimes been… enthusiastic.

But one procedure she has zero regrets about? A post-baby breast augmentation and lift.

She said:

“I thought, ‘I’m going to get some new ones,’ and that was my dream.”

Dream fulfilled. She’s been proudly showing off the results across galas, performances, and red carpets, even switching up the lyrics to her body-positive classic “All About That Bass” to better match 2025’s reality instead of playing 2014’s body politics on repeat, singing "It’s pretty clear, I got some new boobs" at two concerts in May instead of the song's original lyrics, "I ain’t no size two."

And she even revealed that she "didn't believe" what she was singing when she initially wrote the song, saying:

"'All About That Bass,' I didn’t believe that when I wrote it. It [was] like, 'I can’t wait to actually believe this one day' when I perform it 100 times."

At Billboard’s 2025 Women in Music Awards, she doubled down on her transparency, crediting medication, a dietitian, lifestyle changes, and her support system:

“I’ve been on a journey to be the healthiest, strongest version of myself for my kids and for me. Yes, I used science and support (shoutout to Mounjaro!) to help me after my 2nd pregnancy. And I’m so glad I did because I feel great.”

Given Hollywood’s current GLP-1 era—where everyone from reality stars to sitcom uncles is suddenly “just drinking more water and walking,” sure Jan—Trainor’s honesty is refreshing. She’s not pretending the weight “just fell off because motherhood is cardio,” nor is she hiding behind vague wellness jargon.

She’s not the first celebrity to take Mounjaro, and she absolutely won’t be the last. (At this point, the real plot twist would be a star saying they haven’t taken a GLP-1.) Still, the criticism lingered, and it helped shape her newest single.

This week, Trainor released “Still Don’t Care,” the lead track from her upcoming album Toy With Me. It’s classic Meghan: bubblegum-bright, confidence-laced, and carrying a middle finger dipped lovingly in glitter. The song leans into the self-empowerment themes that launched her career while addressing the whiplash of public commentary head-on.

She sings:

“You could say what you want, say I’m so hard to like / You could tear me apart, but I sleep well at night (Woo)... Say I’m doin’ too much, and you’re probably right / That’s the same sh*t I’ve heard my whole life / Said I was too thick, then I got way too thin / And I try to stand out, but I wanna fit in.”

In other words, the internet has had notes on her body since Obama’s first term, and she’s officially done taking notes.

You can listen to the full song here:

- YouTubeMeghan Trainor

In an interview with the Associated Press, she said the wave of negativity directly fueled her writing process:

“I was seeing a lot of hate all over the world, but I was getting a lot of hate when I started posting more pictures of ... my fitness journey and my health journey. And I didn’t really expect that.”

Because nothing turbo-charges creativity like strangers online deciding your progress photos are a personal attack.

She also told People that her page, typically a wholesome sanctuary of mom content and sparkly pop energy, abruptly turned into something resembling a Reddit comment section:

“People started commenting about my body, saying I'm too thin, and that they don't recognize me anymore… I was confused and sad… It’s almost worse now.”

The final straw came after the 2025 Baby2Baby Gala, when commenters declared her “unrecognizable” as if she’d appeared wearing someone else’s face like a Mission: Impossible mask.

And if the comments section is any indication, social media is still split between cheering her on, diagnosing her from afar, or fighting about Mounjaro like it’s a team sport.

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And if Trainor’s honesty about Mounjaro feels refreshing, it’s because she’s far from alone in the Great Celebrity GLP-1 Migration.

Stars like Oprah, Sharon Osbourne, Chelsea Handler, and Real Housewives staple Dolores Catania have openly acknowledged using some form of GLP-1 medication, while others (looking at you, half the cast of Beverly Hills) keep preaching “balanced lifestyles” with a wink so dramatic it might as well count as cardio.

Even actors like Anthony Anderson and comedians like Tracy Morgan have chimed in about the drug’s impact.

Morgan, never one to beat around the bush, joked about his own experience on the Today Show, saying:

“I’ve been on Ozempic for a while now. It cuts my appetite in half. Now I only eat half a bag of Doritos!”

At this point, the real shock isn’t that Meghan Trainor used science to help her lose weight; it’s that she actually said it out loud. Trainor’s transparency might be the most radical part of her entire glow-up.