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Journal Scan / Review · May 12, 2020

Photoprotection Beyond Ultraviolet Radiation

Journal of the American Academy of Dermatology

TAKE-HOME MESSAGE

• In addition to ultraviolet (UV) light, visible light also contributes to photodermatoses and induces erythema in light-skinned individuals and hyperpigmentation in dark-skinned individuals. Current UV filters used in sunscreen, both chemical and mineral filters, are not designed to reduce visible light-induced effects. Tinted sunscreens combine UV filters with a blend of iron oxides and pigmentary titanium dioxide, which function as visible light filters. In clinical studies, tinted sunscreens have demonstrated suppression of visible light–induced pigmentation and prevented melasma relapse better than untinted sunscreen.

• In patients with visible light–induced or aggravated dermatoses, application of untinted sunscreen will only protect from UV light. These patients should be educated to apply a tinted sunscreen of SPF greater than 30 in addition to using other photoprotective measures.

– Margaret Hammond, MD

Written by

 

 

Deborah S. Sarnoff MD, FAAD, FACP

It is well-known that sunlight (composed of ultraviolet, visible, and infrared radiation) can lead to extrinsic aging, photodamage, and skin cancer. As dermatologists, we usually implicate UVA and UVB as the culprits for all of the damage. However, recently, we have become more aware of the dangers of visible light exposure. Televisions, computer display screens, smartphones, electronic notebooks, and other digital devices emit a significant amount of blue light. Visible light, in and of itself, can cause long-lasting hyperpigmentation in those with dark skin tones and immediate erythema in light-skinned individuals. Broad-spectrum sunscreens, including micronized zinc oxide and titanium dioxide, do not adequately protect against visible light. In order for a sunscreen to protect against visible light, it must actually be visible on the skin. By adding a tint composed of iron oxide pigments or pigmentary titanium dioxide to a broad-spectrum sunscreen, visible light is blocked.

This is wonderful news for most women. The tint not only protects against erythema and hyperpigmentation, but it can also simultaneously cover or conceal acne blemishes. Also, it can neutralize the red appearance of rosacea and it can hide areas of PIH. In addition, many of the tinted sunscreens are mattifying and actually diminish oil production and minimize the appearance of pores, rendering the skin to appear more attractive. There is also an added benefit of convenience for those with a busy lifestyle in applying a single, "one and done" product that combines moisturizer, sunscreen, and foundation. Some women may not like the color match of the tint. If that is the case, we should instruct our patients to apply a tinted foundation on top of the sheer or micronized broad-spectrum sunscreen as an extra layer of protection to effectively block visible light exposure.

I am not certain that men will be as accepting of a tinted sunscreen. In my experience, some of my male patients feel that it is "too much like putting on makeup." Others complain that the tinted product stains their shirt collars. They are embarrassed when they sweat on the golf course or tennis court and they wipe their brow and have "makeup" on their hands.

For those patients who struggle with melasma or PIH, or for those who suffer from photodermatoses (with action spectrum in the visible light range), such as solar urticaria or cutaneous porphyria, a broad-spectrum sunscreen with an SPF of 30 or greater with added tint is the logical product to recommend. It is nice to see that sunscreen manufacturers are now offering elegant tinted sunscreens—some with a choice of a few shades—and many with added antioxidant ingredients to neutralize free radical damage and even further protect the skin.

Abstract

Both ultraviolet radiation and visible light have biologic effects on the skin. Visible light can induce erythema in light skinned individuals and pigmentation in dark skinned individuals. Broad spectrum sunscreens protect against ultraviolet radiation and do not adequately protect against visible light. For a sunscreen to protect against visible light, it must be visible on the skin. Inorganic filters (also known as mineral filters), namely, zinc oxide and titanium dioxide, are used in the form of nanoparticles in sunscreens to minimize the chalky and white appearance on the skin; as such, they do not protect against visible light. Tinted sunscreens use different formulations and concentrations of iron oxides and pigmentary titanium dioxide to provide protection against visible light. Many shades of tinted sunscreens are available by combining different amounts of iron oxides and pigmentary titanium dioxide to cater to all skin phototypes. Therefore, tinted sunscreens are beneficial for patients with visible light-induced photodermatoses and those with hyperpigmentation disorders such as melasma and post-inflammatory hyperpigmentation.

Journal of the American Academy of Dermatology

Photoprotection Beyond Ultraviolet Radiation: A Review of Tinted Sunscreens

J Am Acad Dermatol 2020 Apr 23;[EPub Ahead of Print], AB Lyons, C Trullas, I Kohli, IH Hamzavi, HW Lim 

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Benjamin Hidalgo-Matlock
Skin Care Physicians of Costa Rica

Clinica Victoria en San Pedro: 4000-1054
Momentum Escazu: 2101-9574

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