Peptide Hair Serums on TikTok: Density vs. Resistance Claims Reviewed

A viral TikTok clip by creator Lalmaseli compares two popular hair serums: The Ordinary Multi-Peptide Serum and Kérastase Genesis Sérum Anti-Chute. The video claims The Ordinary targets hair follicle density and fullness using “advanced peptide technologies,” while Kérastase focuses on reducing hair fall with Aminexil and ginger root. The clip’s bottom line: The Ordinary for density (more hair), Kérastase for resistance (less hair fall). But what does the research actually support?

What the clip claims

The clip positions The Ordinary as a science-backed, affordable option for increasing hair mass and volume, implying its peptide blend directly stimulates follicles to produce more hair. It also suggests Kérastase works primarily on root reinforcement to prevent breakage, with less emphasis on peptide mechanisms.

What research neighborhood actually covers

Peptides like copper peptides (e.g., GHK-Cu) have been studied for wound healing and hair follicle stimulation in vitro and in small human trials. However, The Ordinary’s Multi-Peptide Serum contains a proprietary blend—including acetyl tetrapeptide-3, trifluoroacetyl tripeptide-2, and others—that has limited published clinical evidence specifically for hair density. A 2015 study on a similar peptide complex (including acetyl tetrapeptide-3) showed increased hair count and thickness, but it was industry-funded and small. For Kérastase, Aminexil is a well-known ingredient in anti-hair-loss products, with some clinical data supporting reduced hair fall, but the peptide component is less central.

Limits of the evidence

Neither product has robust, peer-reviewed trials demonstrating “more hair” or “less hair fall” in diverse populations. Most studies are short-term, sponsored, and use subjective endpoints. The distinction between density and resistance is oversimplified; hair loss often involves both follicle miniaturization and breakage. Additionally, individual results vary based on underlying causes (e.g., androgenetic alopecia, telogen effluvium), which the clip does not address.

Research-use caveat

For researchers and RUO customers, these consumer serums are not equivalent to purified peptides used in controlled studies. The concentrations, delivery systems, and excipients differ. Always verify the specific peptide sequences and purity for any experimental use. This article is for informational purposes only and does not constitute medical advice.

Open the full video fact-check page (transcript, takeaways, embedded clip).