A method for making a skin moisturizing formulation is provided, comprising: providing a dermatologically acceptable vehicle; selecting a skin moisturizing agent based on its ability to absorb and retain moisture, wherein the skin moisturizing agent selected is a cationic dextran polymer, comprising a dextran polymer functionalized with quaternary ammonium groups; providing the selected skin moisturizing agent; combining the dermatologically acceptable vehicle and the skin moisturizing agent to form a skin moisturizing formulation; wherein the skin moisturizing formulation contains 0.05 to 10 wt %, based on weight of the skin moisturizing formulation, of the skin moisturizing agent. Also provided is a method for moisturizing skin.