evidence: A. No. These conclusions come incorrectly from studies where individuals who used sunscreen had a higher risk of skin cancer, including melanoma. This false association was made because the individuals who used sunscreen were the same ones who were traveling to sunnier climates and sunbathing. In other words, it was the high amounts of sun exposure, not the sunscreen, that elevated their risk of skin cancer. [...] A. No, there are excellent studies that sunscreen protects against all three of the most common skin cancers: squamous cell carcinoma, basal cell carcinoma, and melanoma. The degree of protection that sunscreen provides is directly related to the degree to which ultraviolet radiation is associated with the formation of the skin cancer. For instance, in prospective studies of sunscreen, the incidence of squamous cell carcinoma is reduced the most—as much as 40% over four years. [...] A. There's a danger in assuming that putting on sunscreen is by itself enough to protect you against the sun. Many studies have demonstrated that individuals who use sunscreen tend to stay out in the sun for a longer period of time, and thus may actually increase their risk of skin cancer.