What did @megsoto actually say?
She's a breastfeeding mom who lost 60 pounds before pregnancy, 30 of which she credits to semaglutide and then tirzepatide. Now she has 25 pounds of postpartum weight that won't budge, and she's heard that GLP-1 molecules are "too large to enter the breast milk." Her nurse reportedly has two or three breastfeeding patients on GLP-1s with no problems, as long as they hit protein and water targets. She's asking other breastfeeding moms about their experiences. She also mentions her compounded semaglutide was combined with B12, and that she believes peptides helped her lupus, inflammation, and joint pain. She openly acknowledges people may find this reckless, and invites the audience to weigh in.
Does the science back this up?
Honestly, not enough to feel confident either way, and that's the real story here. The "molecule too large" claim is scientifically plausible but not proven in humans. Semaglutide has a molecular weight of roughly 4,114 daltons, which is large for a drug, and larger molecules generally transfer into breast milk at lower rates. But molecular weight is only one factor. Protein binding, lipid solubility, and oral bioavailability in the infant all matter too.
As of early 2025, there are no published pharmacokinetic studies of semaglutide or tirzepatide specifically measuring concentrations in human breast milk. The FDA label for Ozempic states data are simply unavailable. Animal studies in rats did show semaglutide in breast milk, but rodent lactation physiology differs substantially from humans. The American College of Obstetricians and Gynecologists recommends against GLP-1 use during breastfeeding specifically because of this evidence gap, not because harm has been demonstrated, but because safety has not been demonstrated either. That's a meaningful distinction that the video glosses over.
What did they get wrong (or right)?
Give credit where it's due: she's not wrong that molecular size matters for drug transfer into breast milk. That's a legitimate pharmacology concept. She's also right that calorie restriction can reduce milk supply, which is well-documented. A 2012 study by Neville et al. in the Journal of Nutrition confirmed that severe caloric restriction during lactation negatively affects milk volume.
Where she goes wrong is treating anecdote as safety data. A nurse reporting that "two or three" patients had no visible side effects is not a clinical signal. Subclinical effects, including changes to infant gut hormone signaling, would not be detectable without controlled measurement. GLP-1 receptors are present in the infant gastrointestinal tract. If any semaglutide does transfer, the downstream effects on a developing infant's GI system are genuinely unknown.
The claim that peptides helped her lupus and inflammatory markers is unverifiable from this video. It may reflect real symptom improvement, but attributing that directly to semaglutide while also changing diet and losing 30 pounds makes causation impossible to untangle. We won't say it's false, but we won't let it stand unchallenged either.
What should you actually know?
The honest answer is that nobody has done the study yet. That's not reassuring, and it shouldn't be treated as a green light. Here's what the evidence does tell us: GLP-1 agonists are peptide-based drugs that may have low oral bioavailability if they do appear in breast milk, which would limit infant absorption. But "may" is doing a lot of work in that sentence.
The compounded semaglutide with B12 combination she mentions adds another layer of uncertainty. Compounded formulations are not FDA-approved and can vary in concentration and purity between compounding pharmacies. They are not interchangeable with brand-name products, and their safety profiles in breastfeeding populations specifically are even less studied.
If you are a postpartum patient considering a GLP-1, the right move is a conversation with a physician who can weigh your specific situation, not a TikTok comment section or a nurse's informal anecdote count. Postpartum metabolic health is real and worth addressing. That doesn't mean the timing has to be right now, during active breastfeeding, when your infant has no say in the matter.
What's the bottom line?
@megsoto is asking a reasonable question badly dressed up as permission-seeking. The underlying science she cites is real but incomplete. No human data confirm GLP-1s are safe in breast milk. No human data confirm they're harmful either. Regulatory agencies, including the FDA and ACOG, land on "avoid until we know more." Peer anecdote from a small informal patient pool is not the same as safety evidence. Anyone making this decision deserves accurate framing of what we know and what we don't.