A: Over-the-counter brightening lotions are supposed to fade freckles and brown spots, even out skin tone, and add a glow to your complexion. Any fading you get is going to be minimal; even prescription topicals can take two months or longer to yield results, says Cherie M. Ditre, MD, assistant professor of dermatology at the University of Pennsylvania School of Medicine. But you'll probably notice an immediately gratifying—if subtle—effect: Many of these formulas are infused with ingredients that capture light and illuminate your skin instantly. (We especially like Good Skin All Bright Moisture Cream, $24, and Shiseido White Lucent Brightening Protective Moisturizer SPF 16, $48.)
Bottom line: If a lotion seems to brighten you up, enjoy it while it lasts; your glow is mostly cosmetic and therefore temporary.