Sunlight contains two types of UV rays that affect the skin. UVB causes sunburn. UVA reaches deeper, is present all year round and even through windows, and is a major cause of early signs of ageing.
SPF (sun protection factor) tells you how well a product protects against UVB. UVA protection is often shown by the UVA symbol in a circle. Choose a broad-spectrum product, ideally SPF 30 or higher.
UV filters are often divided into two groups. Mineral filters such as zinc oxide and titanium dioxide sit on the surface and reflect and absorb UV rays. Chemical filters such as avobenzone and ethylhexyl triazone absorb UV rays and convert them to heat. Many products combine several filters for broad, stable protection.
How to use: Apply sun protection as the last step of your morning routine, in winter too. Use enough, about two finger lengths for face and neck, and reapply every few hours when you spend a lot of time outdoors.
Good to know: Sun protection is especially important when you use acids, retinol or other actives that make skin more sun-sensitive.