What did @thekarlatobie actually say?
She didn't make a medical claim. She made a personal one: going from a size 3XL to fitting into a medium after twelve months on Mounjaro. Her exact words were "this is insane" and "I would have never believed I would have fit into a size medium." That's it. No dosage advice, no disease cure claims, no promises to other viewers beyond "do not stop." This is a celebration video, not a medical tutorial.
The only quasi-advice she offers is the encouragement "if you aren't a Wegovy journey girl, do not stop," which appears to be a general pep talk to people already on a GLP-1 medication. She's describing her own non-scale victory, a wardrobe milestone, not a clinical outcome. That matters when we're evaluating what she actually put into the world versus what viewers might infer from it.
Does the science back this up?
A 3XL to medium clothing shift in twelve months is dramatic, but it's not outside what clinical trials have documented for tirzepatide. The SURMOUNT-1 trial showed it's biologically possible, though not guaranteed for everyone.
The SURMOUNT-1 trial (Jastreboff et al., 2022, New England Journal of Medicine) found that participants on tirzepatide 15mg lost an average of 20.9% of body weight over 72 weeks. That's roughly 18 months, but meaningful losses were already accumulating at the 12-month mark. A separate analysis published in Obesity (Garvey et al., 2023) confirmed that tirzepatide produced significantly greater reductions in waist circumference compared to placebo, changes that would absolutely translate into clothing size shifts. Going from a 3XL to a medium requires roughly a 3-to-4 size drop, which corresponds to losing somewhere between 30 and 60+ pounds depending on body shape and brand sizing. That's achievable on tirzepatide for some patients, particularly those starting at higher weights. The science doesn't contradict her story. It actually supports that results in this range exist.
What did they get wrong (or right)?
Honestly? She got the framing right. She repeatedly anchors this as her own experience, not a universal outcome. That's more responsible than a lot of GLP-1 content on TikTok.
What she glosses over is that she's also a self-described diabetic, which means Mounjaro (tirzepatide) was likely prescribed for type 2 diabetes management, not cosmetic weight loss. That clinical context matters because her metabolic starting point, insulin sensitivity, and response curve may differ significantly from someone using tirzepatide off-label for weight loss without diabetes. The results she experienced could reflect both the drug's weight-loss mechanism and its glucose-lowering effects working together. Viewers who aren't diabetic shouldn't assume they'll see identical results. She doesn't make that clarification, but to be fair, she also doesn't claim they will. The omission is worth noting, not condemning. One legitimate concern: clothing sizes vary wildly by brand, so a "size medium" in one retailer could be a large or XL in another. This doesn't undermine her achievement, but it makes the claim harder to evaluate as a data point.
What should you actually know?
Tirzepatide is a dual GIP and GLP-1 receptor agonist, which is pharmacologically distinct from semaglutide (Ozempic, Wegovy). It targets two incretin pathways instead of one, and head-to-head data from the SURMOUNT-5 trial (2024) showed tirzepatide produced greater weight loss than semaglutide in adults with obesity. So the drug class she's using is, by current evidence, among the most effective pharmacological options available for weight management.
But individual results vary considerably. SURMOUNT-1 showed a range of outcomes: some participants lost over 25% of body weight, others lost closer to 5%. Factors like starting weight, adherence, dietary changes, physical activity, and genetics all influence outcomes. Going from 3XL to medium is a real possibility for some people on tirzepatide. It is not a guarantee, and framing it as a typical outcome would be inaccurate. Her story is real. Her story is also an outlier relative to median results.
- Tirzepatide is FDA-approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound).
- It is not a cure for diabetes or obesity. It is a chronic treatment that requires ongoing use to maintain results.
- Stopping the medication typically results in weight regain, as shown by Aronne et al., 2024, NEJM.
Bottom line
This video is a personal milestone share, not a health claim. She's celebrating, and the results she describes are plausible based on clinical trial data. The bigger issue isn't what she said. It's what viewers might project onto it: that Mounjaro will do this for everyone, in the same timeframe, without considering individual medical context. That assumption is where the real misinformation risk lives, and it lives in the comments section, not in her words.