The proportion of polyunsaturated fatty acids (PUFA) in the diet and breast milk of lactating women with traditional fish and cod liver oil consumption was investigated under free-living conditions.

Dietary intake of 77 lactating women was investigated by 24-hour recalls and breast milk samples were taken at the same occasions. Maternal intake data was calculated and fatty acid pattern from breast milk samples analyzed with gas chromatography.

Women using cod liver oil (n = 18) had a significantly higher total PUFA intake (14 +/- 10 vs. 9 +/- 7 g/day; 5.0 +/- 3.4 vs. 3.9 +/- 3.0 Energy%; p < 0.05) than women who did not use it (n = 59). In particular, mothers consuming cod liver oil had higher breast milk proportion of docosahexaenoic acid (DHA, 0.54 vs. 0.30%, p < 0.05). They also had higher breast milk proportions of eicosapentaenoic acid (EPA; 0.16 vs.0.07%; p < 0.05) and docosapentaenoic acid (DPA; 0.22 vs. 0.17%; p < 0.05).

The proportion of PUFA in the diet is significantly higher among women consuming cod liver oil. Its use also gives higher proportion of EPA, DPA and DHA in breast milk without decreasing other important fatty acids. As this may have an impact on the health and development of breast-fed infants in later life, regular maternal cod liver oil intake could be relevant for the infant as well as for the nutritional adequacy of the maternal diet.