The retina is particularly rich in long-chain fatty acids. The phospholipids in retinal tissue contain fatty acids, up to 50% of which may be DHA. This suggests DHA is heavily involved in visual function. Vision would also be impossible without DHA.

A study has shown that infants receiving additional omega-3 acids in their milk have better visual acuity than others at the age of 2 months (San Giovanni, Berkey et al. 2000). With age, the retina continues to need an adequate supply of the fatty acids that make up its cells. For example, sufficient omega-3 reduces the risk of macular degeneration, which is the most frequent cause of blindness in the world today (Smith, Mitchell et al. 2000).