Effect of supplementation with 800 IU alpha-tocopherol in the serum and milk of lactating women
Clinical trial. Lactation. Vitamin E. Food consumption. Lipid profile.
During lactation, there is a physiological reduction of vitamin E in milk and maternal supplementation may be an efficient way to increase this concentration and ensure adequate nutritional intake for the infant. However, its impact on the serum-to-breast-milk ratio is not known. In addition, studies show that the response to supplementation occurs in a differentiated way, suggesting the possibility of being influenced either by the dose of the supplement or by probable factors that may interfere with mechanisms of transfer of the vitamin to the mammary gland, yet unknown. Therefore, the objective of the study was to evaluate the effect of maternal vitamin E supplementation on the relationship between alpha-tocopherol in serum and breast milk, and to investigate the factors associated with increased serum vitamin E and milk. A randomized clinical trial was conducted with 79 lactating women attending a public clinic in Natal-RN, Brazil. Participants were allocated to the supplemented group, which received 800 IU of RRR-alpha-tocopherol (588 mg), and in the control group, which did not receive supplementation. Mature milk and serum were collected in both groups between 30 and 90 days postpartum (collection 1) and the next day collection 1 (collection 2). The supplemented group received supplementation immediately after collection 1. Alpha-tocopherol was analyzed by High Performance Liquid Chromatography and the lipid profile was also determined by commercial kits and formulas. Food consumption was obtained from the 24h recall. To evaluate the effect of supplementation on milk, participants in the supplemented group were also divided into quartiles, according to the percentage of increase of alpha-tocopherol in milk between collection 1 and collection 2 (quartile 1 and quartiles 2-4). There was no difference in lipid profile, dietary intake of vitamin E, concentration of alpha-tocopherol in milk and serum between groups in collection 1, and between collection 1 and 2 of the control group (p> 0.05), showing the homogeneity of groups. There were no cases of SVD in the evaluated women, but the majority had inadequate vitamin E intake (<16 mg). In the supplemented group there was an increase of the serum vitamin, where in the collection 1 the average was 1136.8 μg / dL and in the collection 2 was 2080.3 μg / dL (p <0.001), as well as in the milk that went from 300.8 μg / dL to 646.3 μg / dL after supplementation (p <0.001), with increased milk supply being observed. After supplementation, there was a positive correlation between alpha-tocopherol in milk and serum and with dietary vitamin E. Only alpha-tocopherol in milk and serum from collection 1, respectively, were determinants for the increase of vitamin in milk and serum after supplementation. It was observed that the dietary intake of vitamin E was associated to the greater effect of milk supplementation. These findings demonstrate that in cases of high ingestion it is possible to have a higher uptake of circulating alpha-tocopherol by the mammary gland, contributing to the association between serum vitamin and breast milk. In addition, the amount of pre-existing alpha-tocopherol in milk was found to be more effective in vitamin E supplementation in mature milk, suggesting that the mobilization of the vitamin into the mammary gland seems to occur without restrictions. This clinical trial was recorded at http://www.ensaiosclinicos.gov.br/rg/RBR-38nfg2/ (RBR-38nfg2).