防曬是所有皮膚科醫生最一致同意的保養步驟，但對敏感肌來說，選擇一款不刺激的防曬品，並不像選擇 SPF 數字那麼簡單。
防曬劑分為兩大類。化學性防曬（Oxybenzone、Avobenzone、Octinoxate 等）通過吸收紫外線並轉化為熱能來保護皮膚。這類防曬質地輕薄、不泛白，但部分化學紫外線吸收劑被研究與皮膚刺激性相關，對受損屏障的敏感肌風險較高。
物理性防曬（礦物防曬，Zinc Oxide、Titanium Dioxide）通過反射和散射紫外線來保護皮膚。它們不被皮膚吸收，作用停留在表面，被認為是對敏感肌和嬰兒皮膚最安全的選擇。過去物理防曬最大的缺點是泛白（White Cast）和質地厚重，但隨著微粒化（Micronized）和奈米化技術進步，現代物理防曬的質地和外觀已大幅改善。
對敏感肌的建議是：優先選擇純礦物防曬（Zinc Oxide 為主要成分），避免含有酒精和香料的配方，尋找同時含有保濕成分的配方以減少乾燥感。
防曬不是可選項。對於已經受損的皮膚屏障，每天暴露在紫外線下，是讓修護進度倒退最快的方式。
Sunscreen is the one skincare step with the most consistent agreement across dermatology. For sensitive skin, however, choosing a non-irritating formula is not as simple as selecting an SPF number.
Sunscreen filters divide into two categories. Chemical UV filters (oxybenzone, avobenzone, octinoxate) absorb UV radiation and convert it to heat energy. They produce lightweight, sheer formulas, but some chemical UV absorbers have been associated with irritation, posing a higher risk for compromised sensitive skin barriers.
Physical sunscreens (mineral filters: zinc oxide, titanium dioxide) work by reflecting and scattering UV radiation. They are not absorbed by the skin, remain at the surface, and are considered the safest option for sensitive and infant skin. Their historical drawbacks — white cast and heavy texture — have been substantially mitigated by micronization technology in modern formulations.
For sensitive skin: prioritize pure mineral sunscreen with zinc oxide as the primary filter, avoid formulas with alcohol and fragrance, and look for formulas that include moisturizing components to reduce dryness.
Sunscreen is not optional. For a compromised skin barrier, daily unprotected UV exposure is the fastest way to undo any repair progress.