The present invention relates to an iron-based composition, for use in conditions of total or relative iron deficiency. In particular, the present invention relates to a solid composition, preferably in the form of powder or granules, for use in the treatment of disorders or diseases related to or derived from an iron deficiency. The composition of the present invention is suitable for pediatric subjects, adolescents, athletes, men, women, pregnant women and elderly. Finally, the present invention relates to a process for preparing said solid composition.