In this chapter, a review is made on various aspects of chia seed in order to provide an overall, yet comprehensive view, about this important commodity with the aim of updating the current state of knowledge on its composition, possible nutraceutical properties, and potential benefits for human health. Based on this approach, the discussion includes some comments on the main historical aspects, morphology of the seed, its importance in the diet of humans and stresses the main results issued from investigations on its three main components; lipid, protein, and fiber. The chapter closes with a discussion on the potential benefits for human health, highlighting the contradictions that still exist in this area and the need for continued research in this direction and considerations on the role of chia seed as a functional food.