The US government has officially identified ultraviolet radiation (UVR) both from the sun and from tanning machines as a known cause of cancer in humans. UVR produces DNA damage that may lead to mutations (abnormalities) in genes involved in the development of skin cancer. Therefore, along with other sun safety strategies, sunscreens that absorb or block UVR serve an important protective function.
Most people use the term "sunscreen" to denote sunblock, sun cream or suntan lotion". These can range from a cream, lotion, spray, or other topical product that absorbs or reflects some of the sun's ultraviolet (UV) radiation and thus helps protect against sunburn. Diligent use of sunscreen can also slow or temporarily prevent the development of wrinkles, moles and sagging skin.
The more accurate denomination is to distinct between "sunscreen" and "sunblock" based on their mode of action. Here, we explain the difference.