Iron Oxide

Iron oxide is the skin colored pigment in cosmetic foundations. It comes in red, yellow, and brown, and these colors (in combination with white) are used to mix all shades of skin tones. We know you’re wondering why a makeup ingredient is on this guide — well, keep reading.

Your skin is gonna love this: While it isn’t usually thought of as a skin care active, it’s been found to absorb high energy visible light in the blue/violet region. The rays from this spectrum can make skin pigmentation worse, so applying foundation with this active may be a helpful extra step when you’re outside, as the sun is by far the greatest source of visible light.