Skin Hyperpigmentation: What it is, common treatments, and how OS-01 improves skin hyperpigmentation.

We all know that UV exposure (whether it's from the sun or a tanning bed) will darken skin, resulting in a tan. But do you know why UV exposure darkens skin? It all comes down to melanin production - UV exposure increases the skin's melanin production in skin and the more melanin you have, the darker your skin will be! (1)

Written by Kiran Kumar.
Kiran is studying Biotechnology Engineering at UC San Diego. She is highly enthusiastic about longevity sciences, specifically reproductive aging! You can find more work from Kiran at

Reference Lab

FEB 4, 2022

Hyperpigmentation is an age-related condition in which excess Melanin collects in deposits around the skin. This results in darkened patches or spots around the skin, often referred to as “age spots” or “sun spots”. (2)

Anyone who’s been a victim of the “mask tan” (coined from the Covid pandemic), can see why this could be an issue. Having said that, skin hyperpigmentation is usually harmless, but it can also be a symptom of more serious skin conditions, so if you have any concerns, please consult your physician.

The good news? OneSkin’s products serve as essential moisturizers that harness the power of a proprietary peptide, OS-01, which can help reduce the Melanin deposits over time. To understand how OS-01 reduces hyperpigmentation, it’s important to understand some background on why and how melanin is produced.

01Melanin and Melanocytes.

Melanin is an overarching term for a group of pigments which occur in human hair, skin, and eyes. It’s made by special cells called Melanocytes, which make and transfer Melanin pigments to neighboring cells. (1)

But, what propels this process into Hyperpigmentation and what initially causes it?

It depends. There are three types of Hyperpigmentation, and all three have a different cause.

  • Sun spots - caused by sun exposure, more specifically UV exposure.
  • Melasma - caused by hormone changes. For instance, pregnancy can impact Melanin production.
  • Post-inflammatory - caused by injury or inflammation. (2)

02Common Treatments.

Kojic acid, Retinol, and Hydroquinone are the most common treatments for all three types of Skin Hyperpigmentation. But what are the risks associated with these treatments? Let’s take a closer look at some of the research into these products.

  • Kojic Acid: This acid is a known skin irritant. It can actually cause dermatitis, including eczema, especially for those with sensitive skin. In fact, Kojic Acid has been banned as a potential carcinogen in Japan, Korea, and Switzerland. (3)
  • Retinol: Retinol is a very common anti-aging skincare ingredient, often held as the anti-aging gold standard for its famed ability to renew skin cells and improve skin plumpness, subsequently decreasing the appearance of fine lines and wrinkles. Unfortunately, Retinol has a dark side. It works by stripping your skin’s top layer and stimulating cell renewal to replace those layers with new skin cells. However, overuse of retinol can strip your skin too quickly and reduce barrier function significantly, potentially compromising your long-term skin health. Most commonly, people have observed heightened skin sensitivity, redness, excessive peeling, and inflammation from using retinol. Additionally, OneSkin’s scientists found that though Retinol is effective at increasing the activity of genes associated with collagen and hyaluronic acid production, it also significantly increases the activity of genes which are linked to aging and inflammation, therefore retinol’s long-term damage can easily outweigh its short-term benefits. (Read more here.) (4)
  • Hydroquinone: Hydroquinone is usually used to lighten the skin. However, prolonged use (over 3 months), can cause ochronosis, a disease that causes blue/black discoloration of facial tissue,

03Study: OS-01 vs Common Treatments

The study

In this study, One Skin investigated the efficacy of OS-01, Kojic Acid, and Retinoic Acid at suppressing melanin production. The study was performed in three steps:

  • Mimic hyperpigmentation: To induce melanin production and mimic hyperpigmentation, OneSkin’s scientists exposed melanocytes (cells that produce melanin) to IBMX (isobutylmethylxanthine), a molecule which mimics one of the main pathways induced by UV radiation and also imitates a pathway induced by ACTH (adrenocorticotropic hormone).
  • Expose melanocytes to different treatments: After the melanocytes were exposed to IBMX to induce melanin production, OneSkin’s scientists exposed the melanocytes to either nothing (positive control), Retinoic Acid, Kojic Acid, or the OS-01 Peptide.
  • Measure resulting melanin production: The amount of melanin production was then measured both intracellularly (inside the cells) and extracellularly (outside of the cells). Note that measuring the extracellular melanin production is crucial for analyzing a molecule’s ability to treat hyperpigmentation, since melanocytes transfer the melanin pigment to neighboring cells.

The results

As the below graph indicates, the OS-01 peptide reduced the amount of melanin production in the melanocytes significantly more than Retinoic Acid, Kojic Acid, and the control, demonstrating OS-01’s superiority in repairing hyperpigmentation in skin. This means that the common alternatives, Retinol and Kojic Acid, not only underperformed relative to OS-01, but, as we established previously, can also compromise long term skin health. In contrast, OS-01 has been shown to greatly improve health markers in skin by increasing skin’s epidermal thickness, improving skin’s barrier function, and increasing skin’s natural ability to produce collagen, elastin, and hyaluronic acid. This data indicates that OS-01 is a superior alternative to Kojic Acid and Retinol to treat hyperpigmentation while maintaining long-term skin health.

Melanocytes were first exposed to IBMX to induce melanin production, then exposed to either nothing (positive control), Retinoic Acid, Kojic Acid, or the OS-01 Peptide. Melanin production was subsequently measured intracellularly and extracellularly. The melanocytes that were exposed to OS-01 reduced the amount of melanin production both intracellularly and extracellularly significantly more than those that were exposed to Retinoic Acid, Kojic Acid, and the positive control.

04Don’t just take it from us.

When it comes to OS-01, the data and the customers agree! Here’s what people think about OneSkin’s Topical Supplement, a daily facial moisturizer powered by the OS-01 peptide:

“Using Oneskin has taken the age spots away from my arms. They are almost clear and getting even better. Thank you so much.”

  • ~Chuck
  • Male
  • Age 65+

"My rosacea has improved using this product, not including my hyperpigmentation has improved as well which was a surprise because I never expected to ever see my normal skin color again after a failed IPL years ago. This is the best product I've ever used."

  • ~Joshua C.
  • Male
  • Age 25-34

"OneSkin is amazing! It made my melasma fade like no other cream."

  • ~Luciana W.
  • Female
  • Age unknown

05Pictures speak louder than words.

In a 12-week clinical study, participants experienced a reduction in hyperpigmentation from using OS-01 Topical Supplement 2x daily.

  • before
  • after
  • before
  • after
  • before
  • after

06Key Takeaways.

  • Hyperpigmentation is an age-related condition in which excess Melanin collects in deposits around the skin, producing what are commonly known as aging spots and sun spots.
  • Common treatments such as Kojic acid, Retinol, and Hydroquinone have risks associated with them, such as damaging long-term skin health, inducing skin-aging, and even darkening the skin.
  • In a study comparing Retinoic Acid, Kojic Acid, and OneSkin’s OS-01 peptide, OS-01 notably outperformed all other treatments in its ability to reduce Hyperpigmentation.

Reviewed by Alessandra Zonari, PhD, Chief Scientific Officer (CSO) and Co-Founder of OneSkin

Alessandra earned her Master’s degree in stem cell biology, and her PhD in skin regeneration and tissue engineering at the Federal University of Minas Gerais in Brazil in collaboration with the 3B’s Research Group in Portugal. Alessandra did a second post-doctoral at the University of Coimbra in Portugal. She is a co-inventor of three patents and has published 20 peer-reviewed papers in scientific journals.

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