Effect of Fish-oil Supplementation During Lactation on Maternal Milk Long-chain Polyunsaturated Fatty Acids Concentration: Results From a Sub-study of a Randomized Controlled Trial in Rural Ethiopia

Abstract Background: Human milk (HM) is the main source of the long-chain polyunsaturated fatty acids (LCPs) docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (AA) for infants and young children in low- and middle-income countries. While the AA concentration in HM seems rather stable, the concentration of DHA is highly variable and influenced by the maternal intake of marine foods. Mothers in low-income settings living far from coastal areas have limited access to marine foods which may put their children at risk of inadequate omega-3 (n-3) LCPs intake.Objective: In a sub-study of an individually randomized controlled trial, we evaluated the efficacy of fish-oil supplementation of lactating mothers on HM n-3 LCPs concentrations in a rural setting in Ethiopia.Methods: Mothers (n = 360) with children 6-12 months old were randomized to receive either an intervention fish-oil capsules [FO: 215 mg DHA + 285 mg EPA] or a control corn-oil capsules [CO: without n-3 LCPs] for 12 months. In a random subsample of 154 participants, we analyzed LCPs in HM and child capillary blood using gas chromatography at baseline, and at 6 and 12 months of the intervention.Results: Compared to the control, FO supplementation increased HM concentrations of DHA by 39.0% (P < 0.001) and EPA by 36.2% (P < 0.001), whereas the AA/(DHA + EPA) ratio decreased by 53.5% (P < 0.001). We also found statistically significant associations between the changes in (DHA + EPA)/AA ratio in the maternal milk and the child capillary blood samples following the supplementation (P < 0.001). However, HM DHA concentrations still remained lower than international norms after the fish-oil intervention.Conclusions: Fish-oil supplementation in lactating mothers improves n-3 LCPs status of HM. It is recommended that future studies evaluate different doses of n-3 LCP and consider the impact of potential effect modifiers such as genetic polymorphism, diet, and others.Trial registration: ClinicalTrials.gov, NCT01817634. Registered 20 March 2013, https://clinicaltrials.gov/ct2/show/record/NCT01817634.