The Science of Iron Oxide in Skin Care

Chances are, you’ve used a skin care or cosmetic product that contains iron oxide – but you may have not known it. Iron oxides are commonly found in tinted sunscreens and makeup products as a natural colorant. They also come along with a few key benefits to the skin, including the ability to block blue light from penetrating your skin and to help keep melasma and other forms of hyperpigmentation at bay. 

Before we can help you decide if iron oxide-containing products could be right for your skin, make sure you know which of the 16 Baumann Skin Types you are first. Then, use the information in this guide as a starting point to decide if and how to incorporate them into your skin care regimen.

Iron oxides, also called ferric oxides, are naturally occurring minerals found in various natural colors, though red is the most common hue used in cosmetics. In skin care and cosmetics, iron oxides are used as pigments to give products a natural tint without synthetic dyes. They are also UV-stable and resistant to oxidation, so they maintain their color in sunlight and don’t easily degrade.

The iron oxides used in cosmetic products are processed to remove impurities, making them safe for cosmetic use. There are three main types of iron oxide pigments commonly used in skin care:

1. CI 77491 (red)

2. CI 77492 (yellow

3. CI 77499 (black)

While they are most commonly used as a tint for sunscreens and makeup, iron oxides also have a few other key benefits for your skin:

• Blocks blue light. Blue light has very short, high-energy waves, so it is able to penetrate deeper into the skin than UVB and UVA rays. Here, blue light can stimulate melanocytes (the cells that produce melanin), which trigger melanin production. This can cause dark spots and other forms of hyperpigmentation like melasma. Iron oxides form a physical barrier over the skip and are able to reflect and scatter blue light, thus reducing its effects on melanocytes and preventing excessive pigmentation.
• Helps to prevent melasma. This ability to shield skin from blue light helps to reduce hyperpigmentation, including melasma. Melasma is often worsened by blue light, which is why dermatologists like Dr. Baumann often recommend tinted sunscreens that contain iron oxides to help prevent melasma from recurring. 
• Antioxidant protection. Studies have found that certain iron oxide nanoparticles have the potential to provide antioxidant protection by reducing oxidative stress, a process in which free radicals damage skin cells and accelerate aging (3).

Iron oxide is considered safe for cosmetic use and has a low hazard rating on the Environmental Working Group (EWG) Skin Deep database. Unlike some chemical sunscreen ingredients and colorants, iron oxides are non-irritating and are generally safe for sensitive skin types. Iron oxides are also non-comedogenic, so they’re unlikely to clog pores.

However, as with any ingredient, there is a small chance of an allergic reaction to certain iron oxides, although this is rare.

Mineral sunscreens, also called physical sunscreens, are a great chemical-free alternative to traditional chemical sunscreens. Mineral sunscreens contain ingredients like zinc oxide and/or titanium dioxide to reflect UV rays away from your skin. However, one of the challenges with these sunscreens is that they tend to create a white hue on the skin. Iron oxides can be added to mineral sunscreens to provide a natural tint that helps to blend the sunscreen with your skin tone for a clearer, smoother finish.

As an added bonus, tinted sunscreens with iron oxide offer both UV and blue light protection, making them ideal for people with melasma or those who spend a lot of time in front of a computer screen.

Some of the best mineral sunscreens that contain iron oxide include:

Iron oxide is also widely used in makeup products like foundations, BB creams, and concealers to provide natural tints. While these products can provide some sun protection, don’t rely on these products alone for full UV protection. This is because you would have to apply much more makeup than most people are comfortable with applying in order to reach the necessary SPF to keep your skin protected.

To keep your skin protected from both sun damage and blue light, you can layer makeup with an SPF sunscreen underneath, or use a tinted sunscreen as a base.

Iron oxide is a common ingredient used in many sunscreens and makeups to provide a natural tint. In addition to its use as a natural pigment, iron oxide also provides benefits such as blocking blue light and helping to prevent melasma and other forms of hyperpigmentation. Choosing a sunscreen that contains iron oxides can protect your skin against both UV light and blue light. Just be sure you are choosing a sunscreen that is right for your skin type so that you will wear it every day!

1. Baumann L. Antiaging Ingredients in Ch. 37 of Baumann's Cosmetic Dermatology Ed 3. (McGraw Hill 2022)
2. Baumann, L. Ch. Cosmeceuticals and cosmetic Ingredients (McGraw Hill 2015)
3. Somu Yadav, Stuti Bhagat, Sanjay Singh, Pawan Kumar Maurya, Comparative Study of Antioxidant Activity of Dextran-Coated Iron Oxide, Gold, and Silver Nanoparticles Against Age-Induced Oxidative Stress in Erythrocytes, The Journals of Gerontology: Series A, Volume 79, Issue 11, November 2024
4. Bernstein, E. F., & Boland, P. (2020). Iron oxides in sunscreen provide enhanced protection against HEV blue light exposure. Journal of Cosmetic Dermatology, 19(7).
5. Hamzavi, I. H., Jang, H. S., & Kang, K. (2020). Impact of iron-oxide containing formulations against visible light-induced skin pigmentation in skin of color individuals. Journal of Drugs in Dermatology, 19(7).
6. Duteil, L., Queille-Roussel, C., & Lacour, J. P. (2020). Photoprotection beyond ultraviolet radiation: A review of tinted sunscreens and foundations containing iron oxide for visible light protection. Journal of the American Academy of Dermatology, 82(6), 1246-1254.