DHA is actively incorporated into the brain and retinal cell membranes during the last trimester of pregnancy and the first two years of life, where it appears to play a structural and functional role. Although DHA can be synthesized in small amounts in vivo, the efficiency of this conversion is very low. Adequate dietary DHA may therefore be essential for optimal cognitive and visual development.

Researchers used a systematic review and meta-analysis of 38 reports, including 53 intervention arms, to examine the effects of supplementation of mothers (13 trials), preterm infants (7 trials), and term infants (18 trials) with n-3 PUFAs, including DHA or EPA, on cognitive and visual development in children.

Analysis of the study results identified significant benefits of supplementation with n-3 PUFAs on neuromotor development and visual acuity during a critical period of brain development: from pregnancy to infancy, and the effects may be stronger in preterm and term infants compared to maternal supplementation (partial results of the analysis are shown in Figures 1–2 below).

Combined with observational studies of maternal diet, these findings support the benefits of n-3 PUFAs on psychomotor and visual development during pregnancy and the first 2 years of life.

Shulkin, M., Pimpin, L., Bellinger, D., Kranz, S., Fawzi, W., Duggan, C., & Mozaffarian, D. (2018). n–3 Fatty acid supplementation in mothers, preterm infants, and term infants and childhood psychomotor and visual development: a systematic review and meta-analysis. The Journal of nutrition, 148(3), 409-418. [Link]