The practice of using urine as a cleanser dates back centuries. Reportedly, an ancient Sanskrit text advises massaging the liquid into the skin, and it's thought that 17th century French aristocrats bathed in the stuff to improve their complexion. Today, web sites tout urine as a cure for rashes and other skin problems.
To find out if this bathroom beauty trick has any merit, we consulted Ahmet Altiner, M.D., an assistant professor of clinical dermatology at Weill Cornell Medical College and owner of UWS Dermatology & Skin Care in New York City.
"Urine contains uric acid, which has an exfoliating effect," says Altiner. So applying it on your skin removes dead skin cells, revealing a fresh layer beneath. "In fact, many beauty products contain urea or uric acid, which is a sterilized kind of urine made in the laboratory," he adds.
But there's no point in collecting your own sample to scrub up with. "A face wash containing glycolic or salicylic acid delivers the same benefit," says Altiner. Plus, the inorganic compounds in pee can irritate the eyes—and may lead to an infection. The bottom line? This is one practice you can, well, safely flush down the toilet.