Peptide stacks on TikTok: what the science actually supports

What did @amylovespeppers actually say?

She listed her current "pepper stack" as GHK-Cu (copper peptide), MT1 (Melanotan 1), Selank ("Salink"), Semax ("Max"), and NAD. She named three separate vendors, praised their certificates of analysis, and dropped a discount code. That is the entire substance of the video.

To be direct: this is a vendor promotion video dressed up as a stack-sharing post. No dosing information was given, no mechanism of action was explained, and no health claims were made explicitly. That last point actually matters for how we evaluate it, because the hashtags like "antiaging" and "womenshealth" do the implicit claiming for her. The audience already knows what these compounds are associated with, and she is counting on that. The video is light on science but also light on overt misinformation, which makes it a more interesting fact-check than most.

Does the science back this up?

The individual compounds in her stack have genuinely interesting research behind them, but the evidence base is thinner and more preliminary than the "biohacking" community typically acknowledges.

GHK-Cu is probably the most studied compound she mentioned. It has demonstrated wound-healing and collagen-synthesis activity in cell and animal studies, and a 2015 review by Pickart and Margolina in Rejuvenation Research summarized its broad tissue-repair activity. Topical GHK-Cu is already in cosmetic products. Injectable systemic use in humans, however, lacks robust clinical trial data.

Selank and Semax are synthetic peptides developed in Russia, primarily studied in Russian literature. Semax has shown neuroprotective effects in rodent models of ischemia (Dolotov et al., 2006, Journal of Neurochemistry). Selank has anxiolytic properties in animal models. Human trial data is sparse and largely unpublished in peer-reviewed Western journals. MT1 (Melanotan 1, afamelanotide) is the most legitimately clinical compound here. It is actually FDA-approved as Scenesse for erythropoietic protoporphyria. Outside that indication, it is not approved for cosmetic tanning or other uses.

What did they get wrong (or right)?

She did not make overt false medical claims, which deserves acknowledgment. She did not tell viewers these compounds treat diseases or quote fabricated studies. That puts her a step above many peptide influencers.

What she got wrong is harder to pin on a single statement but is embedded throughout. Promoting MT1 for general "stacking" purposes ignores that afamelanotide's approval is for a rare genetic disorder, not optimization. Using it recreationally introduces melanocyte-stimulating risks that have not been studied in healthy populations over time. A 2019 paper by Langan et al. in JAMA Dermatology raised concerns about unregulated melanocortin agonists and atypical nevus development.

Recommending a vendor because of "amazing COAs" also overstates what a certificate of analysis proves. COAs confirm purity and concentration from a third-party lab. They do not confirm sterility for injectable use, absence of endotoxins, or long-term safety. The "biohacking" community treats COAs as a safety seal. They are not.

What should you actually know?

These compounds are not FDA-approved for the uses implied by this video. Purchasing injectable peptides from online vendors, regardless of COA quality, bypasses the entire regulatory chain that exists to catch contamination, mislabeling, and dosing errors. That is a real risk, not a bureaucratic abstraction.

GHK-Cu has the strongest evidence base of the compounds listed and the lowest risk profile, particularly in topical form. Semax and Selank are genuinely under-researched in humans, and most of what exists comes from studies conducted in the 1990s and 2000s in Russia without the trial design standards expected in current FDA submissions. MT1's legitimate clinical use is narrow. Buying it from a peptide vendor to add to a "stack" is a different category of activity than using a prescribed, approved medication.

NAD (presumably NAD+ precursor or injectable NAD) has a growing research base. A 2023 randomized trial by Yoshino et al. in Science showed NMN supplementation improved muscle insulin sensitivity in postmenopausal women, but injectable NAD protocols used in the biohacking space are well ahead of that evidence.

• None of these peptides should be self-administered without medical supervision.
• A COA is not a safety clearance for injectable use.
• MT1 is an approved drug for a specific rare condition, not a general wellness compound.
• Vendor recommendations with discount codes are financial relationships, not clinical endorsements.