Chemical sunblocks are actually associated with increased skin cancer. Oxybenzone for instance is a known carcinogen, found in many sunblock products. The only two sunblocks consistently proven safe are the mineral sunblocks: titanium dioxide and zinc oxide. Additionally, zinc supports the immune system. Sun damage is an inflammatory process ( as is acne, pigment formation and rosacea). So not only do mineral sun blocks protect the skin, zinc also gently treats inflammation. The sun emits both UVA and UVB wavelengths. UVA are associated with skin cancer and aging. UVB wavelengths are the ones that burn the skin. When the sun is high, our skin is more likely to burn (more UVB). But when the sun is lower, in the morning and evening (50 degrees above the horizon or less) the UVA waves are at their highest.