Abstract: A process for preparing a stable packaged dosage form, said dosage form comprising an oxidation-sensitive material, for example carotenes and carotenoids in whole dried algae of the genus Dunaliella. The invention also relates to a stable packaged oral dosage form comprising whole dried algae, but substantially no antioxidants exogenous to said whole dried algae and a dosage form consisting essentially of whole dried Dunaliella in encapsulated, tableted or single dosage sachet form and it further relates to a method of treatment or prophylaxis of various conditions, a method for supplementing the diet of a subject, a method for maintaining or improving the general health of a subject, and a method for promoting a fake suntan on a subject, wherein said methods comprise administering to a subject an effective amount of whole dried Dunaliella rich in carotenes.