Method for reducing hair damage when exposed to heat

The present invention provides a method for reducing hair damage upon exposure to heat, the method comprising: providing a cosmetically acceptable aqueous carrier; a thermal protective agent is selected wherein the thermal protective agent is selected based on its ability to impart exothermic protection to hair from heat exposure wherein the thermal protective agent is selected as a functionalized dextran polymer comprising a dextran polymer functionalized with a moiety selected from the group consisting of: (i) a tertiary amine group; (ii) a quaternary ammonium group; and (iii) combinations thereof; providing the selected thermal protective agent; combining the cosmetically acceptable aqueous carrier and the thermal protectant to form an aqueous thermal protectant formulation; providing hair; applying the aqueous thermal protectant formulation to the hair to provide a protected hair; providing a heating hair care appliance; and exposing the protected hair to a temperature of 50 DEG C to 300 DEG C for 1 minut