Medicine Hidden in Cosmetics

Modern analysis confirmed what Egyptians seemed to know by instinct: the lead compounds in their eye makeup had real medical value. Studying kohl samples held at the Louvre, researchers found that the lead salts nudged the body's own immune defenses into action, helping fight bacterial eye infections.

Along the Nile, the hot, dusty air made eye infections common, so this was everyday medicine, not magic. In a 2010 study, French researchers showed that the lead salts in kohl boosted the body's production of nitric oxide, a signal that rallies immune cells to attack invading bacteria.