A composition and method for enhancing the immune system of an individual is provided. The present invention enhances the functioning of the immune system through increasing the production of certain cytokines, inhibiting viral adhesion and interfering in the viral replication process. The severity and duration of infections resulting from the common cold and associated viral infections are also reduced through the oral administration of the composition of the present invention. The composition of the present invention comprises at least an effective amount of an extract of wolfberry (Lycium barbarum), and an effective amount of an extract of elderberry. The present invention may additionally comprise effective amounts of one or more of an extract of blueberry, Echinacea root, and Vitamin C.