Polyunsaturated fatty acids in human milk and their role in early infant development

The lipid fraction of human milk represents the main source of energy for t he newborn infant and supplies essential nutrients such as fat-soluble vita mins and polyunsaturated fatty acids (PUFA).(3) The essential fatty acids l inoleic and alpha-linolenic acids are precursors of long-chain polyunsatura ted fatty acids (LC-PUFA), such as arachidonic (C20:4 n-6) and docosahexaen oic (C22:6 n-3) acids, present in human milk in considerable amounts. LC-PU FA are indispensable structural components of all cellular membranes, and t hey are incorporated in relatively large amounts during early growth of the brain and the retina. Moreover, some LC-PUFA are precursors of eicosanoids , molecules with potent biological activity that modulates various cellular and tissue processes. The supply of long-chain fatty acids has been associ ated with functional outcomes of the recipient infants such as visual acuit y and development of cognitive functions during the first year of life. Her e we discuss the PUFA composition of human milk, factors which determine an d modulate milk PUFA content, and possible effects of milk LC-PUFA on infan t growth and development.