It's opaque: Zinc oxide is what is known as a physical sunblock, meaning light cannot get through it. By preventing ultraviolet light from getting to your skin, it protects your skin from sunburn and other sun damage. Other sunscreens block uv light with chemicals, which some experts believe does not work as well as the physical sunblocks.
Answered 7/5/2012
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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