An oral composition for the prevention, reduction or treatment of radiation injury including one or more compounds that regulates cell differentiation and/or cell proliferation, and one or more antioxidants, optionally formulated in a pharmaceutically acceptable carrier for an oral composition. The composition of the present invention may further include optional ingredients such as flavonoids, flavonoid derivatives, selenium, selenium compounds, anti-inflammatories, organic germanium, Korean ginseng, American ginseng, Siberian ginseng and B-complex vitamins. A method for the administration of an oral composition for the purpose of preventing, reducing or treating radiation injury involves orally administering an effective amount of a composition including one or more compounds that regulates cell differentiation and/or cell proliferation, and one or more antioxidants to a person before, during or after radiation exposure. The compositions and methods can be employed to prevent, reduce or treat radiation injury caused by a wide variety of types of radiation exposure.