Understanding the active ingredients in sunscreen is a bit like learning a foreign language that uses a different alphabet. Suffice it to say in short that sunscreens are made up of a combination of two types of ingredients: those that reflect ultraviolet (UV) rays and those that absorb UV rays. Although that might sound simple enough, there are also two types of rays: UVA rays and UVB rays. UVB causes sunburn at the outer layers of skin, but UVA causes sun damage that reach deeper layers of skin. Both UVA and UVB radiation can contribute to the development of skin cancer. Most sunscreen ingredients protect against UVB rays, but Mexoryl SX (also called ecamsule) absorbs UVA radiation and is therefore included in many sunscreens. Mexoryl SX also doesn’t degrade in sunlight and maintains the majority of its sun filtering capability even 24 hours after initial application. There are no known issues with Mexoryl in terms of toxicity and it does not appear to be absorbed into the skin. Therefore, sunscreens that include Mexoryl are providing a broader spectrum of sun protection, regardless of the SPF factor. In addition to sunscreen, manufacturers have also included Mexoryl in lip balms, lipsticks, and facial moisturizers.