A couple of months ago, my mother was at a doctor's appointment when she noticed that the 70-something lab technician taking her blood had zero wrinkles. My mom asked the woman what she used on her skin, and as she stuck a needle into my mom's arm, she replied: "sunscreen" and then in a whisper, "pee-pee."
This woman had supposedly been "dabbing" her face with urine since she was younger, and now here she was, nearing 80 with the complexion of a 40-year-old. It was the first time I'd ever heard of someone using their own urine for cosmetic purposes, but urine therapy, the umbrella term for using urine topically or orally, is quite common in alternative medicine. It's an ancient practice whose origins are largely attributed to Indian culture: the Damar Tantra, an ancient Sanskrit text, claims that drinking one's own urine is the cure to all diseases. The Greeks, Egyptians, and Romans used it, too; Pliny the Elder recommended it to cure burns, inflammation, and skin diseases. Which presumably means Pliny the Younger was on board, and if urine worked for the Plinys, it's worth a shot.