Clinical overview of effects of dietary long-chain polyunsaturated fatty acids during the perinatal period.

The current report provides a brief background introducing 30 years of research on long-chain polyunsaturated fatty acids (LC-PUFA) and infant development, but focuses mainly on challenges for future studies. Infants fed formulas containing only vegetable fats were found to have lower docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (20:4n-6) status than infants fed human milk. Studies soon focused on efforts to improve LC-PUFA status and evaluate functions suggested by early primate studies of DHA deficiency. Despite evidence for the importance of these fatty acids for development, particularly DHA, several recent meta-analyses conclude dietary supplementation does not enhance development. Future studies should employ (1) more finely grained measures of brain development as opposed to global measures, and (2) tests that evaluate development later in childhood when children are able to be tested on more complex behaviors (if found effective these would also be evidence of early brain programming). (3) Studies are needed to understand the cause of high variability in transfer of DHA to the fetus. (4) Finally, the role of single-nucleotide polymorphisms of the fatty acid desaturase genes 1 and 2 of mother and infant needs study to determine how they affect requirements for these fatty acids by the fetus/infant.