If sunburn occurs after 10 minutes without sunscreen, an SPF 15 sunscreen delays burning to 150 minutes. Risks of Underuse Dermatologists say sunscreens are not foolproof. Most people don't slather on enough. Key body areas, like the ears and back, often get missed. And sunscreens are sweated, rubbed, and washed off.
Psychology poses other problems.
However, it does grow in size and destroy normal tissue. Examples of chemical sunscreens include para-aminobenzoic acid esters, salicylates, and cinnamates. Sunscreens are available in creams, lotions, gels, wax sticks, and sprays. To better advise his active patients, Siegel personally tests how well sunscreens stay on during his sweaty racquetball sessions. I rub it on my forehead.