The existence of the macula lutea, or “yellow spot,” in the human retina has been known since the end of the 18th century (1). The nature and identity of macular pigment carotenoids is now well established (2-8). It was recognized very early that the macula lutea filtered the light entering the eye prior to perception and thereby affected color matching (9). Walls suggested in the 1930s that the macular pigment might be responsible for reduction of chromatic aberration and improved visual acuity (10,11). In the early 1980s, it was postulated that the macular pigment might protect the structures of the retina lying posterior to itself by absorbing excess blue light (1,12). Our developing understanding of the etiologic development of age-related macular degeneration is further illuminating the significant role of the macular carotenoids in ocular health (13). The presence of carotenoids in lens and other ocular tissues is now also recognized (14). Whether it will be possible to establish a functional relationship between the presence of these carotenoids and maintenance of the health of the eye presents an unfinished challenge. This chapter will focus on carotenoids of the retina and lens where an evolving body of epidemiological data supports the premise that they play a role in maintaining ocular health (see Chapter 19).
