Tinted sunscreens are having a moment. These mineral-based sunscreen formulations have an added color base that can help even out skin tone while protecting your skin. And thanks to their ability to block visible light, they may help certain skin conditions. Could the days of unsightly sunscreen residue be in your past?
What is visible light, and how can it affect your skin?
Ultraviolet (UV) radiation and visible light are both part of the electromagnetic spectrum. UV radiation is composed of three different wavelengths: UVA, UVB, and UVC. UVC is mostly absorbed by the ozone layer, so UVA and UVB are the primary wavelengths that penetrate the skin’s surface. The harmful effects of UV light on the skin have been well documented. UVA is primarily responsible for premature skin aging, and UVB has been implicated in sunburns and skin cancer. The primary source of UV radiation is sunlight.
Visible light is also emitted by the sun. It is the portion of the electromagnetic spectrum that can be perceived by the human eye. Visible light may also come from artificial sources, including medical devices, screens, and light bulbs. Visible light has several skin-related therapeutic uses at specific wavelengths, including treatment of superficial blood vessels, removing unwanted hair, and treating acne and precancerous skin lesions.
Visible light penetrates much deeper into the skin than UV radiation, and can also have negative consequences for your skin. For example, visible light has been implicated in exacerbating disorders of excess skin pigmentation, including melasma and post-inflammatory hyperpigmentation (dark spots). One study showed that visible light caused more noticeable, persistent hyperpigmentation that UVA alone, especially in people with deep skin tones. This may be especially true for blue light (the kind emitted by device screens), which seems to promote pigment production more than other wavelengths of the visible light spectrum.
Components of tinted sunscreens
Broad-spectrum, non-tinted sunscreens contain filters that block UVA and UVB, but these preparations are not designed to block visible light. To block visible light, a sunscreen must be visible on skin. The problem? The particles in broad-spectrum, non-tinted sunscreens are “nanosized” (made smaller) to help reduce the white appearance of sunscreen. Thus, non-tinted sunscreens are formulated to be invisible on skin, and therefore cannot block visible light.
Tinted sunscreens combine broad-spectrum mineral UV filters, like zinc oxide and titanium dioxide, with added pigments — pigmentary titanium dioxides and iron oxides — that create the visible, skin-tone color that can reflect away visible light. The colored base of tinted sunscreens is created by mixing different amounts of black, red, and yellow iron oxides with pigmentary titanium dioxide, resulting in a tinted sunscreen that can be matched to any skin tone.
While these pigments are considered inactive, there have been two reports of allergic reactions to iron oxides contained in mascara products. Otherwise, these ingredients appear to be well tolerated.
Tinted sunscreens may help certain skin conditions
Tinted sunscreens can provide anyone an instant, skin-evening glow, while simultaneously helping to protect your skin from both sunlight and artificial light.
Growing evidence suggests that tinted sunscreens may be particularly important for people who are prone to hyperpigmentation or melasma. That’s due to their ability to block visible light, which is known to exacerbate these conditions. Tinted sunscreens have been found to reduce relapses of melasma more than non-tinted, broad-spectrum sunscreens. Tinted sunscreens have also been shown to reduce hyperpigmentation, both on the skin surface and under a microscope. Iron oxide, in particular, appears to be particularly effective at blocking blue light.
What should I look for in a tinted sunscreen?
Choosing a broad-spectrum, tinted sunscreen may help prevent age-related skin damage (thanks to UVA filters), may help to prevent cancer-inducing skin changes (thanks to UVB filters), and may help protect against excess pigmentation (thanks to the color base that blocks visible light).
Tinted sunscreens are now widely available to purchase online or in retail stores. If you are prone to hyperpigmentation or melasma, choose a tinted sunscreen that contains iron oxide (you’ll see it on the ingredient list).
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The post Tinted sunscreens: Benefits beyond an attractive glow appeared first on Harvard Health Blog.
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