Department of Dermatology, Henry Ford Hospital, Detroit, Michigan.
Innovation and Development, ISDIN, Barcelona, Spain.
J Am Acad Dermatol. 2021 May;84(5):1393-1397. doi: 10.1016/j.jaad.2020.04.079. Epub 2020 Apr 23.
Ultraviolet radiation and visible light both 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 but 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 postinflammatory hyperpigmentation.
紫外线和可见光都会对皮肤产生生物学效应。可见光可以使浅色皮肤的个体产生红斑，使深色皮肤的个体产生色素沉着。广谱防晒霜可以预防紫外线辐射，但不能充分预防可见光。为了使防晒霜能够预防可见光，它必须在皮肤上可见。无机滤光剂（也称为矿物滤光剂），即氧化锌和二氧化钛，以纳米颗粒的形式用于防晒霜中，以最大限度地减少皮肤上的粉质感和白色外观；因此，它们不能预防可见光。有色防晒霜使用不同配方和浓度的氧化铁和颜料性二氧化钛来提供对可见光的防护。通过组合不同量的氧化铁和颜料性二氧化钛，可以获得多种色调的有色防晒霜，以满足所有皮肤光型的需求。因此，有色防晒霜对因可见光引起的光致皮肤病患者以及患有色素沉着障碍如黄褐斑和炎症后色素沉着过度的患者有益。
