Chemical sunscreens rely on synthetic chemicals, or filters, to absorb rays. These filters soak into skin and can cause irritation and allergies. Some, like oxybenzone, have been linked to hormone disruption and cancer. Mineral sunscreens use natural ingredients like zinc oxide and titanium dioxide to physically deflect rays. These minerals sit on skin rather than sinking into it, but since they create a physical barrier, they can leave a white residue or cake on skin. Some products minimize these effects by using extremely small particles of minerals, known as nanoparticles. Which is best for you is a matter of personal choice: While mineral sunscreens tend to be safer because they don't contain possibly harmful filters, they can be difficult to spread and look white on skin. There is also concern that mineral nanoparticles may sink into skin, too, causing unknown health effects, but most brands don't specify whether they contain nanoparticles. For the best mineral face and full-body sunscreens that spread clear, see our top picks.