That's what the US Food and Drug Administration found in late May, issuing warning letters to the manufacturers of four of these products. The supplements -- Advanced Skin Brightening Formula, Sunsafe Rx, Solaricare and Sunergetic -- were "putting people's health at risk by giving consumers a false sense of security that a dietary supplement could prevent sunburn, reduce early skin aging caused by the sun, or protect from the risks of skin cancer," according to an FDA news release .