Peptide therapy TikTok claims: separating hype from human data

What did @hxris.h actually say?

The creator said GHK-Cu will make your hair "thicker," skin "more shinier," and "tighten the wrinkles," while NAD+ is "good for your cognitive function and your energy levels." They also pointed to their own skin as evidence, saying they're "looking a lot more younger" and "a lot more clearer." The video ends with an invitation to message them for a source to buy from, which is worth flagging immediately.

These are two distinct compounds being bundled together as the must-have stack for 2026. GHK-Cu is a naturally occurring copper peptide. NAD+ is a coenzyme, not technically a peptide at all, though it often travels in the same wellness circles. Mixing them in one "you need these" recommendation, without any dosing caveats, medical context, or disclosure of what they're actually selling, is the first problem with this video.

Does the science back this up?

For GHK-Cu specifically, there is real research here, but it is mostly in vitro and small-scale. For NAD+, the human evidence is growing but still far from settled, especially for the cognitive claims.

On GHK-Cu: Pickart and Margolina (2018, Cosmetics) summarized decades of research showing GHK-Cu stimulates collagen and glycosaminoglycan synthesis in fibroblast cultures, and a small double-blind trial by Leyden et al. (1994, Skin Pharmacology) found topical copper peptide formulations modestly improved skin laxity. However, most positive findings are in cell cultures, not randomized controlled trials in humans. The "thicker hair" claim has some backing from a study by Uno and Kurata (1993, Journal of Investigative Dermatology) showing copper peptides prolonged the anagen phase in animal models, but human trial data is thin.

On NAD+: Yoshino et al. (2021, Science) showed NMN supplementation improved muscle insulin sensitivity in postmenopausal women. Brakedal et al. (2022, Cell Metabolism) found NR raised brain NAD+ levels in Parkinson's patients. Cognitive benefits in healthy people, however, remain largely unproven in robust human trials.

What did they get wrong (or right)?

They got the general direction right on GHK-Cu and skin. The peptide does have mechanistic plausibility for collagen support and there is enough topical evidence to say it is not snake oil. Credit where it is due.

What they got wrong is the certainty. Saying it "is gonna" thicken your hair and tighten wrinkles as if these are guaranteed outcomes skips over the fact that most strong evidence is preclinical. The anecdotal "this is how my skin is looking" approach is not evidence, and presenting personal appearance as proof of a compound's efficacy is a well-worn social media tactic that misleads viewers about causation.

The NAD+ cognitive claim is the weakest link. Saying NAD+ is "good for your cognitive function" in healthy people is not well-supported by current human RCT data. The mechanism is plausible, mitochondrial energy metabolism does involve NAD+, but mechanistic plausibility and demonstrated benefit in healthy humans are not the same thing.

The call to message them for a purchase source at the end without any disclosed affiliation or medical disclaimer is a real problem, not just a nitpick.

What should you actually know?

GHK-Cu has one of the more credible research profiles in the topical peptide space. If you are considering it for skin support, the topical route has the most human evidence behind it. The hair growth claims need more human data before they should be stated as fact.

NAD+ precursors like NMN and NR are not the same as supplemental NAD+ itself, and the bioavailability of oral NAD+ is a legitimate scientific debate. Studies like Trammell et al. (2016, Nature Communications) confirmed NR raises blood NAD+ in humans, but whether that translates to the specific benefits claimed in short social media videos is a different question entirely.

Neither compound has been approved by the FDA to treat, cure, or prevent any disease. If you are considering either for a specific health concern, that conversation belongs with a licensed medical provider, not a DM thread with a TikTok creator who is offering to tell you where to buy.

• Ask any provider about their regulatory status and whether the source is a licensed compounding pharmacy operating under appropriate oversight.
• Be skeptical of any creator who uses their own face as clinical evidence.
• "Do your research" is reasonable advice, but it should come before the sales pitch, not be used to offload responsibility onto the viewer.