Peptides for hair growth: separating signal from TikTok noise

What did @sofiahairhealth actually say?

Sofia made three main claims: that peptides are "scientifically proven" to help hair growth, that they work by keeping hair in the anagen phase longer and resisting DHT and inflammation, and that one product in her lineup contains ingredients that "mimic growth factors," which she called "really astounding" and "one of a kind." She reviewed three over-the-counter topical serums: The Ordinary Multi-Peptide Serum, Vegamour GRO+ Advanced Serum, and CÉCRED Restoring Hair and Edge Drops. She framed the CÉCRED drops as the standout because of the growth factor-mimicking ingredient, without naming what that ingredient actually is.

To be fair, she kept things mostly accessible and didn't promise a cure or quote fake numbers. But the phrase "scientifically proven" is doing a lot of heavy lifting here, and the vague gesture at "very new" unnamed ingredients deserves scrutiny.

Does the science back this up?

Partially, yes. Topical peptides have legitimate research behind them, but the evidence is nowhere near as settled as "scientifically proven" implies. The most studied peptide in this space is GHK-Cu (copper tripeptide-1), which has shown real promise in small trials.

A 2007 study by Lesiak et al. in the Journal of Investigative Dermatology found GHK-Cu stimulated hair follicle proliferation in vitro. A 2015 review by Pickart and Margolina in the journal Biomolecules confirmed GHK-Cu influences several wound-healing and growth pathways. That's meaningful, but most of these studies are small, use isolated cells or animal models, and don't always translate cleanly to a product you spray on your scalp once a day.

On DHT resistance: peptides don't block 5-alpha reductase the way finasteride does. Saying peptides "resist" DHT is a stretch. Some peptides may reduce scalp inflammation that worsens androgenic alopecia, but that's an indirect effect, not hormone blocking. The anagen phase claim has some basis in GHK-Cu research but hasn't been definitively confirmed in large randomized controlled trials in humans.

What did they get wrong (or right)?

The anagen phase explanation was mostly right in concept. Peptides like GHK-Cu do appear to support follicle signaling that influences hair cycle duration. Credit where it's due.

The DHT claim is where things get sloppy. She said peptides can "resist damage from hormones like DHT." There's no credible evidence that any of the peptides in these three products meaningfully block DHT or androgen receptor activity. Anti-inflammatory peptides may reduce the inflammatory cascade that accompanies androgenic alopecia, but that is not the same as resisting DHT. Conflating the two misleads people who are dealing with real pattern hair loss and might delay seeking treatments with actual evidence behind them, like minoxidil or FDA-approved options.

The growth factor-mimicking ingredient she raves about for CÉCRED is almost certainly a reference to something like a synthetic biomimetic peptide or a plant-derived growth factor analog. Without naming it, viewers have no way to look up the evidence themselves. That's a problem. Exciting ingredient, zero accountability.

What should you actually know?

Topical peptide serums are not a replacement for clinically validated treatments for androgenic alopecia or female pattern hair loss. Minoxidil remains the most evidence-backed topical option for those conditions, with multiple large RCTs behind it. Peptide serums may offer complementary benefits, particularly for scalp health and mild thinning not driven by androgens, but the evidence base is still thin compared to first-line treatments.

If you're buying one of these products for general hair health and you're not dealing with significant hormonal hair loss, the research on GHK-Cu and related peptides is genuinely interesting and the risk profile is low. The Ordinary's serum is a reasonable low-cost option given its ingredient list. But if you have androgenic alopecia, a TikTok peptide serum is not your primary tool. Talk to a dermatologist or trichologist before spending money based on a product review that can't name its star ingredient.