This invention relates to a topical cosmetic or dermatological composition comprising a 1 3 diglyceride having the general formula (I) in which the radicals R1 and R2 represent independently of one another a C13 to C40 saturated and linear alkyl radical and at least one cosmetic or dermatological excipient for a topical application on the skin. This invention also relates to such a composition or a 1 3 diglyceride having the formula (I) for its use in protecting the skin in countering the weakening of the skin barrier and in preventing or reducing the penetration of exogenous molecules into the skin following a weakening of the skin barrier.
