People knew that others harm themselves by sun exposure, but did not fully recognize the potential harm of sun exposure to themselves.
People think they're safe.
But they're not as safe as they think they are because they don't use sunscreens daily and then use them as their only means of sun protection. Sunscreen use has been typically limited to water-related sports, rather than everyday activities. Minimize sun exposure between 10 a.m. and 4 p.m., when the sun's rays are the strongest. Apply a broad-spectrum sunscreen of SPF 15 or greater about 20 minutes before sun exposure. Reapply after swimming and after two hours, even on cloudy days.