Fatty acid composition in maternal milk and plasma during supplementation with cod liver oil

Objective: We investigated how cod liver oil influences the amount of essential fatty acids in mothers' breast milk. Design and Intervention: Lactating mothers (n = 22) were randomized into four groups 3-8 weeks after parturition. They were supplemented for 14 days with 0, 2.5, 5 and 10 ml cod liver oil (7.7 g eicosapentaenoic acid (EPA, 20:5n-3), 10.2 g docosahexaenoic acid (DHA, 22:6n-3) and 22.9 g n-3 fatty acids in total per 100 mi). Results: In maternal plasma phospholipids there was an increase in the content of EPA and DHA in the group supplemented with 10 ml cod liver oil daily (P less than or equal to 0.05). DHA concentrations in breast milk pre-supplementation ranged from 0.15 to 1.56 wt% and increased in all supplemented groups (P less than or equal to 0.05). The concentration of EPA in breast milk increased in the groups supplemented with 5 or 10 ml cod liver oil (P less than or equal to 0.05), whereas the concentration of arachidonic acid (AA, 20:4n-6) did not change in any of the supplemented groups. Total intake of DHA adjusted to body mass index (BMI), correlated to DHA concentrations in plasma (r = 0.49, P = 0.02) and breast milk (r = 0.45, P = 0.04). The concentration of tocopherol did not change during the supplementation period, neither in plasma nor in breast milk. Conclusion: Dietary intake of DHA is reflected in the concentration of DHA in breast milk, without affecting the concentration of AA or tocopherol.