What did @holisticglpgirly actually say?
The creator walked viewers through reconstituting what she called "MT1 or Melena Tane 1" — almost certainly Melanotan II (MT-II), not MT-1, which is a separate compound. She said it "increases the melanin production in your skin, giving you a gradual even beautiful tan," can "help prevent the risk of sunburn," delivers a "beautiful firm glow," and that "some people also talk about its cognitive benefit and help with social anxiety." She links to a vendor in her bio. The disclaimer that she is "a random person on the internet" does not change the fact that 697,000 people just watched a tutorial on injecting an unregulated peptide.
Worth noting: she appears to conflate MT-1 (afamelanotide) and MT-II. They are different molecules with different receptor binding profiles and risk signatures. That confusion matters when your audience is injecting based on your tutorial.
Does the science back this up?
Partially, but the framing strips out essentially all of the risk context. The melanin-stimulating mechanism is real. The "sunburn prevention" claim is where things get complicated. And the cognitive and anxiolytic claims are thin and almost entirely preclinical.
MT-II is a synthetic analog of alpha-melanocyte-stimulating hormone (alpha-MSH) and binds melanocortin receptors MC1R through MC5R. Its pigmentation effect is documented. Afamelanotide, a closely related compound, is FDA-approved under the name Scenesse for erythropoietic protoporphyria specifically because it reduces photosensitivity. But Scenesse is not MT-II, it is administered as a slow-release implant under physician supervision, and it is approved for a rare disease, not recreational tanning.
The anxiolytic and cognitive claims rest largely on rodent studies. Bhatt et al. (2009, Pharmacology Biochemistry and Behavior) found MC4R agonism reduced anxiety-like behavior in rats. Human data for MT-II on mood or social anxiety is essentially nonexistent in peer-reviewed literature.
What did they get wrong (or right)?
She got the core mechanism right and got almost everything else either wrong or dangerously incomplete. Credit where it is due: melanocortin receptor agonism does stimulate melanogenesis. That part of the claim is accurate.
But "help prevent the risk of sunburn" is misleading without a serious caveat. Increased melanin does provide some photoprotection, but MT-II does not replace sunscreen and has been associated with activation of pre-existing nevi and melanoma concerns. A 2015 case series in JAMA Dermatology (Boos et al.) documented melanoma development in individuals using unlicensed melanotan products. The FDA issued a warning about these products in 2018 specifically citing risks of melanoma, changes in moles, and cardiovascular effects including priapism and elevated blood pressure.
The "firm glow" claim is unsubstantiated in clinical literature. And calling MT-II a cognitive or anxiolytic agent based on rodent data while pointing 697,000 people toward a vendor link is a significant overstep.
What should you actually know?
MT-II is not FDA-approved for tanning, sunburn prevention, or any cosmetic use. It is sold as a "research peptide," which is a legal gray zone that means it has not cleared safety and efficacy review for human use. That status does not make it safe. It means it has not been proven safe.
Known adverse effects reported in the literature and in FDA communications include nausea, facial flushing, spontaneous erections (a documented side effect the creator did not mention), elevated blood pressure, and mole changes. The mole changes are not trivial. Dermatologists have raised repeated alarms about stimulating melanocyte activity in people with dysplastic nevi or a family history of melanoma.
If you are interested in photoprotection backed by actual regulatory review, afamelanotide (Scenesse) exists as a physician-prescribed option for a specific indication. That is a different product, a different administration route, and requires a doctor. The version being sold through TikTok bio links is none of those things.
Bottom line
The creator is enthusiastic, the disclaimer is present, and the melanogenesis mechanism is real. But this video teaches nearly 700,000 people to inject an unregulated compound while understating documented risks including potential melanoma activation, cardiovascular effects, and the simple fact that "research peptide" does not mean "safe for humans." The sunburn prevention framing is particularly problematic because it may lead people to skip actual photoprotection. That is a real harm risk dressed up as a wellness tutorial.