Dry skin

• In 2002 Acta dermato Venereologica published a double-blind study in which 197 patients with atopic dermatitis were treated for 30 days with either a 20 percent glycerin cream, a cream base with no active ingredient or a cream with 4 percent urea and 4 percent sodium chloride. While the glycerin and urea/sodium chloride creams were equally effective in treating dry skin, the glycerin had a lower rate of adverse skin reactions. [Source]
• In 2001 the International Journal of Cosmetic Science published a double-blind, placebo-controlled trial which showed that 10 days of treatment with a 20 percent glycerin-containing cream was superior to a placebo in improving skin hydration, but not transepidermal water loss, in a group of 17 healthy volunteers. [Source]