Let’s be honest: there are a lot of skincare products on the market. At The Chalkboard Mag, we test new formulas almost daily—some buzzy, some bland, and a few that actually surprise us. OneSkin was one of those rare surprises. What instantly caught our attention? They didn’t just remix existing ingredients or lean on trends. They developed one.

That’s right. The team behind OneSkin isn’t made up of marketers or influencers. It’s led by four female scientists—experts in skin regeneration, stem cell biology, immunology, and bioinformatics—who set out on a mission to redefine aging. When their lab research revealed that many so-called “anti-aging” products weren’t doing much (and in some cases were actually harmful at the cellular level), they rolled up their lab coats and got to work. More than five years and 900+ peptides later, they developed OS-01: the first patented peptide scientifically proven to reverse the skin’s biological age.1

Unlike the average beauty brand, OneSkin doesn’t just claim results—they back them up with peer-reviewed, published data, transparently linked right on their site. In fact, they’ve conducted multiple lab and clinical studies—measuring everything from skin’s biological age to collagen production—with results that are easy to understand and access. In a landscape filled with smoke and mirrors, this level of transparency and clinical validation is rare—and refreshing.

What Is OS-01?

OS-01 is OneSkin’s patented peptide—and the first of its kind proven to reverse skin’s biological age. It works by targeting cellular senescence (the accumulation of damaged, aging cells), helping reduce inflammation markers, improve skin function, and restore visible youthfulness from the inside out.1,2

Why Cellular Senescence Matters

We talk a lot about skin aging—but what actually causes it? A major culprit is cellular senescence. With age (and exposure to stressors like UV and pollution), some of our cells become damaged and enter a “zombie-like” state. These senescent cells don’t die, but instead linger, spreading inflammation and aging signals to surrounding healthy cells.

The result? Reduced collagen and elastin, compromised barrier function, thinning skin, hair loss, and yes—those fine lines and wrinkles. What makes OS-01 so groundbreaking is that it directly targets the accumulation of these dysfunctional cells, reducing their overall levels and helping restore healthier, more youthful skin function.

What the Studies Show

OneSkin’s results aren’t just surface-level. Here’s what their OS-01 peptide has been shown to do in lab studies on human skin samples:

+ Reduces biological skin age by up to 2.5 years using OneSkin’s MolClock algorithm, which measures skin’s biological age.1

+ Increases epidermal thickness by up to 28%, helping skin look and act younger, firmer, and more resilient.1

+ Reduces a key aging biomarker (CDKN2A) while increasing collagen and hyaluronic acid production markers (COL1A1 and HAS2).1

That means it doesn’t just make skin look better—it helps it behave better. Curious how this stacks up to your current routine? [Explore the OneSkin lineup here].

Why They Invented Their Own Peptide

We asked OneSkin what drove them to invent a peptide from scratch. Their response: “OS-01 is the first and only peptide scientifically proven to reverse skin aging by targeting cellular senescence—a key driver of aging. We screened over 900 candidates to find one that meaningfully reduced senescent cells.”

Other peptides on the market may hydrate or signal collagen production. But OS-01 does something deeper: it restores skin health by addressing a root cause of aging. And because the team has a biotech background, their approach to formulation is unusually rigorous. Every ingredient is tested in-house, iterated in full formulas, and only included if it demonstrates clear benefits to skin biology in the lab.

How It Fits Into a Skincare Routine

If you’re new to the brand, start with OS-01 FACE—It’s is a multitasking moisturizer designed for daily use. It addresses the most common signs of aging on the areas most exposed to environmental stressors—think face, neck, and chest. Along with deep hydration, it supports skin thickness, promotes collagen, and targets aging at the cellular level [Shop here]. For the eye area (which tends to age faster), the OS-01 EYE delivers a higher concentration of the peptide to help reduce signs of fatigue and keep skin firm and resilient [Shop here].

If you’re someone who never skips lip balm, OS-01 LIP SPF might be your new favorite [Shop here]. It hydrates, protects from sun damage, and strengthens the delicate skin on your lips—all without the sticky, glossy feel.

There’s also the OS-01 HAIR Scalp Serum, which brings the same peptide-powered approach to the scalp to support healthier hair and follicle function. We’re looking to test this one next and see how it stacks up alongside the rest of the lineup.

The best part? OS-01 plays well with others. You don’t have to ditch your favorite actives like retinol or acids. In fact, this peptide can help buffer irritation and rebuild the barrier while those ingredients get to work. And every formula is super clean—fragrance-free, non-comedogenic, and safe for sensitive skin.

OneSkin’s lineup may be tight, but it’s mighty—with each product built to do more than just sit pretty on your shelf.

How OS-01 Compares to Supplements

We’ve covered senolytic supplements before—formulas designed to reduce cellular senescence throughout the body. But OS-01 offers a different kind of benefit. While oral supplements act systemically, they often face bioavailability hurdles (like digestion and metabolism).

OS-01 bypasses all of that by being applied directly to the skin, where cellular senescence is most visible. The result? A more targeted, efficient approach to reducing signs of aging at the surface level, while still complementing any internal longevity protocols you may already follow.

Aging, Meet Your Match

OneSkin doesn’t just talk about results—they prove them. In a space overflowing with empty promises and trend-driven formulas, this brand stands out for its science, transparency, and purpose. OS-01 isn’t just a breakthrough peptide—it’s the result of years of research, thousands of hours in the lab, and a bold belief that aging doesn’t have to mean decline.

And maybe that’s what struck us most. This isn’t just about smoother skin or a better serum. It’s about changing the conversation around aging—treating skin like the living, vital organ it is, and giving it the tools it needs to thrive.

If you’re looking for something real—something backed by science and built with intention—OS-01 just might be your new favorite formula. We’ve seen a lot. But this one? This one made us pause.

1 Zonari, A., et al. Senotherapeutic peptide treatment reduces biological age   and senescence burden in human skin models. npj Aging, 9(1), 1-15. 2023. doi:10.1038/s41514-023-00109-1

2 Zonari A., et al. Double-blind, vehicle-controlled clinical investigation of peptide OS-01 for skin rejuvenation. J Cosmet Dermatol. 2024; 23: 2135-2144. doi:10.1111/jocd.16242 

Explore the claims at oneskin.co/claims