Science tells us that healthy mud, or wet soil, is rich with minerals and other nutrients, alive with worms, fungi, and bacteria, and all of their by-products. It has been used for cleansing and healing rituals for millennia. And Egyptian queen Cleopatra allegedly used wraps made from Dead Sea mud as a beauty treatment.Board-certified dermatologist Dr. Dhaval Bhanusali, a mask treatment developer, says that the benefits of mud body treatments are usually immediate and obvious: The skin changes, blood flow changes, and muscles relax. “They’re a great exfoliator,” Bhanusali says. A key is in the minerals. Kaolinite, bentonite, magnesium, potassium, and other minerals in mud and clay masks imperceptibly abrade the skin and dislodge impurities, he says, and the minerals in mud also help retain heat, which helps relax muscles, stimulate blood flow, and improve lymphatic system cleansing.