Why TikTok Trends Don’t Belong in Your Skincare Routine

In the beauty industry, trends come and go faster than the seasons. After nearly three decades working in dermatology and cosmetic science, I’ve seen them all — from bizarre to brilliant. Some make sense. Many do not. And a few, frankly, are alarming. 

At every trade show, people ask about the next big thing. But the real question should be: is it safe, effective, and ethical? Let’s look at some of the most talked-about miracle ingredients of recent years — and what science actually says. 

A year ago, TikTok users were applying beef tallow to their faces, calling it a natural moisturiser. Articles claimed it was better than high-tech formulations. In truth, it’s neither new nor beneficial. In Northern Europe, animal fats were used generations ago only because there were no alternatives. 

From a biochemical view, beef tallow consists of saturated fatty acids that can trigger inflammation (as described in Skin Pharmacology and Physiology, 2018). Its composition isn’t always compatible with human skin lipids, meaning it can disrupt the barrier, oxidise quickly, and even produce a strong rancid odour. 

And let’s not forget — there’s nothing cruelty-free about it. So this "natural revival" was really just nostalgia dressed up as skincare science. 

Another buzzword that once swept the beauty world was “nano.” The promise: ultra-tiny molecules that penetrate deep for miraculous effects. The reality: A 2022 review on nanotechnology in cosmetics reports that nanoparticles can pose health risks due to their potential toxicity, which depends on size, dose, surface properties and exposure time. It stresses that long‑term effects and environmental impact are still not well understood.

Most scientific and regulatory reports conclude that nano-sized metal oxides in sunscreens (such as titanium dioxide and zinc oxide) mostly remain in the outermost layer of healthy skin. When the skin is damaged or heavily affected by UV, though, deeper penetration has been observed, and some studies have detected small amounts of metal or particles beyond the surface layers.The result? Potential neurotoxicity affecting brain and nervous system. 

Today, “non-nano” sunscreens dominate formulators’ booths — a perfect example of how enthusiasm for innovation can outpace safety data. Modern encapsulation technologies have improved, but “nano” still treated with caution and regulatory oversight. The SCCS scientific advice explicitly calls for case‑by‑case safety assessment of each nanomaterial in cosmetics, because small changes in size, coating, or formulation can change toxicity and penetration markedly

The sudden excitement about PDRN (polydeoxyribonucleotide) from salmon DNA sounds futuristic, but it’s actually an old idea — patented back in the 1980s. The claim is that salmon DNA fragments rejuvenate or regenerate skin. Yet, independent evidence is extremely limited; most studies are industry-funded. 

What’s worse, sourcing this ingredient means killing fish, often for just milliliters of extract. That’s hardly in line with the sustainability or cruelty-free values modern skincare champions. And scientifically, peptides and amino acids already provide targeted, well-understood skin-repair benefits without ethical compromise. 

The irony? We now have over 600 peptides registered for cosmetic use worldwide, all with mapped mechanisms of action and proven safety. They outperform salmon-derived DNA in every category that matters: efficacy, predictability, and ethics. 

The latest trade shows were flooded with “exosome” claims. Exosomes are micro-vesicles naturally used by cells to send messages — found in animals, plants, and even us. Used properly, this concept holds medical promise. But the beauty market often runs ahead of the research. 

Human- and animal-derived exosomes are banned for cosmetic use in nearly every developed region. The risk of transmitting viruses, prions, or genetic material is too high. The U.S. FDA and the European Commission explicitly warn against them.  When China — once among the more permissive markets — bans something on safety grounds, that says a lot. 

Plant-derived exosomes, now used in some creams, sound safer, but in most cases they’re not real exosomes at all — just lipid-based delivery particles mimicking them. Every plant extract already contains natural exosomes that carry antioxidants, vitamins, and acids. Paying hundreds of dollars for “exosome serum” is, in many cases, paying for marketing vocabulary. 

While these trends make headlines, the true heroes of modern skincare rarely do: peptides, probiotics, and biotech-derived actives. These innovations are backed by decades of independent research and transparent testing. They work with skin biology, not against it. 

Supporting the skin microbiome with prebiotics and postbiotics, using customized peptide cocktails, and employing biotechnological ceramides — this is where science-driven skincare thrives. These aren’t fleeting trends; they’re the foundation of sustainable skin health and longevity.

Trends are seductive. They come wrapped in “natural” or “next-gen” promises. But beauty that lasts comes from science — not social media. Let’s leave behind animal fats, extracted DNA, and mysterious “nano” particles, and focus on ingredients that restore, protect, and respect our skin’s biology. 

Trends fade. Science stays.