INTRODUCTION
Light from across the electromagnetic (EM) spectrum can cause detrimental cutaneous effects including photocarcinogenesis and photoaging. Prevention strategies can help reduce malignancy risk and clinical manifestations of photoaging such as rhytides.1 Increased education about skin health, photodamage, and the impact photoaging has on aesthetics drives demand for sun care products.
The optical spectrum portion of light includes ultraviolet (UV) with wavelengths of 10 to 400 nm; visible light (VL) with wavelengths of 400 to 700 nm; and infrared (IR) with wavelengths of 700 nm to 1 mm.2 Commercial organic and inorganic sunscreens are designed to protect up to wavelengths of 380 nm.2 However, UV only accounts for approximately 5% of the solar radiation reaching earth's surface.3 The remaining solar radiation is approximately 50% IR and 45% VL.3
It is well established that exposure to ultraviolet radiation (UVR) can cause skin cancer and photoaging. While traditional sunscreens can block much of this UVR, recent studies have shown that skin damage is also induced by other forms of radiation. VL and IR may not always be covered by current, traditional sunscreens. Research in this area is notably important for skin of color (SOC), which may be particularly sensitive to the photodamaging effects of these other forms of radiation. This article will review established photoaging prevention strategies and examine innovative products beyond traditional sunscreens and their potential role in photoprotection in all skin types.
Importance of Photoaging Prevention
Cumulative solar radiation can lead to skin cancers, including melanoma, basal cell carcinoma, and squamous cell carcinoma. Treating these malignancies and other pre-cancers can cause scarring and deformities in the skin. Additionally, photoaging can manifest as unwanted aesthetic concerns including rhytides, atrophy, laxity, dyspigmentation, telangiectasias, roughness, and mottled appearance of the skin.1 Preventative photoprotection strategies are essential to thwarting the risk of developing such conditions.
Established Photoaging Prevention: Sunscreen and UV
Most current sunscreen products protect against UVB and, to a lesser extent, UVA solar radiation.2 Sunscreen is graded by sun protection factor (SPF). SPF measures the amount of UVR needed to induce erythema, or burn, on protected skin relative to unprotected skin.4 SPF does not distinguish between protection against UVB and other forms of radiation.5 The Food and Drug Administration (FDA) and the United States Preventive Services Task Force (USPSTF) recommend broad-spectrum filters with an SPF of 15 or above. The American Academy of Dermatology (AAD) recommends using an SPF of 30 and above.
