Do polynucleotide or salmon DNA facial treatments actually work?
There are cautious indications that polynucleotide injections may improve the skin around the eyes, but well-controlled evidence is still lacking. If you are considering the treatment, ask your practitioner specifically about the supporting evidence and remain critical of commercial interests.
Polynucleotides (also known as salmon DNA injections, or sold under brand names such as REJURAN) are injected into the skin and are said to stimulate skin repair, reduce wrinkles, and improve skin texture. That sounds promising, but the research is currently limited and has considerable methodological shortcomings.
For the under-eye area and crow's feet, there are small observational studies and a prospective study in 42 patients that showed improvement up to six months after treatment. Patients were generally satisfied, and side effects were minimal. However, none of these studies included a placebo group, so it is unclear how much of the effect is attributable to the treatment itself and how much to the placebo effect or the passage of time.
The most randomised study, on crow's feet in 218 participants, was later found to have been retracted. That means its results must be considered void. For facial redness and enlarged pores, there are no clinical trials; the only available data come from surveys of cosmetic physicians. Between 77% and 90% of them rated the treatment as effective, but physician opinions are not clinical evidence. In addition, several authors of those studies had a binding relationship with the manufacturer of the product, which undermines the independence of those findings.
For scars and burns, there are isolated case reports without a control group. And although a review article suggests that polynucleotides as an adjunct to another treatment (radiofrequency microneedling) may offer additional benefit, the contribution of polynucleotides specifically cannot be isolated.
In short: for the under-eye area and fine lines, there are cautious indications that the treatment has some effect, but without well-controlled research it remains uncertain how large that effect is. For the other applications, the evidence is even thinner.
All claims are based on observational studies, case reports, a scoping review, and physician opinion surveys. The only randomised study (PMID 39313949) has been retracted. Multiple studies have potential conflicts of interest with manufacturers. No study includes a placebo group.
Do exosomes in skincare really work?
There are preliminary indications that exosomes may do something for the skin, but the clinical evidence is very thin: one small study without a control group and otherwise mainly animal research. Do not buy into the hype just yet, but keep an eye on the research over the coming years.
Does a vampire facial (PRP) work against skin ageing?
PRP injections produce a modest, likely genuine improvement in skin texture and elasticity, but do not work for everything (hydration and pigmentation spots respond poorly). If you want to try it, choose a clinic that provides clear information about the protocol used.
Do peptides in skincare actually do anything?
Peptides in creams have a plausible mechanism on paper, but clinical evidence for topical use is thin. If you want to do something about skin ageing, oral collagen currently has the stronger foundation, though that too should be interpreted with some caution.
What actually works against skin aging?
Using sunscreen daily is the best-supported way to slow skin ageing, supplemented by not smoking, moderate alcohol consumption and sufficient sleep. Cosmetic options such as thread lifts and honey in creams have a weaker or not yet sufficiently proven basis and call for a critical weighing of the risks.
Does red light therapy really help against skin ageing?
Red light therapy shows improvement in skin texture and wrinkles across multiple studies, but the effects are modest and the evidence is not yet broad enough to be certain. Combining it with near-infrared light appears to have the strongest support; experimenting at home is possible, but dramatic results should not be expected.
Does skin cycling actually work better for your skin?
Skin cycling as a protocol has not been scientifically tested, so no proven benefit can be attributed to it. Some of the ingredients it features, such as ceramide moisturisers and nicotinamide, do have solid evidence behind them individually.