Efeito da suplementação com 800 UI de Alfa-Tocoferol no soro e leite de mulheres lactantes

Abstract

During lactation, there is a physiological reduction of vitamin E in milk and maternal supplementation is an efficient way to increase this concentration and ensure adequate nutritional intake for the infant. However, the impact on the serum-to-breast-milk ratio is not known. Additionally, studies show that the response to supplementation occurs in a differentiated way, suggesting the possibility of being influenced both by the dose of the supplement and by other factors that may interfere with mechanisms of transfer of the vitamin to the mammary gland, as yet unknown. Therefore, the objective of the study was to evaluate the effect of maternal vitamin E supplementation on the relationship between alphatocopherol in serum and breast milk, and to investigate the factors associated with increased serum vitamin 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. Alphatocopherol was analyzed by High Performance Liquid Chromatography and the lipid profile was determined by commercial kits and formulas. Food consumption was obtained from the 24-hour 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 alphatocopherol 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. The evaluated women did not present vitamin E deficiency (SVD), but the majority presented 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). After supplementation, there was a positive correlation between alpha-tocopherol in milk and serum and with dietary vitamin E. When assessing the factors associated with the effect of supplementation, only alpha-tocopherol in milk from collection 1 and food consumption of vitamin E showed a significant relation with the increase of vitamin in milk, whereas serum from collection 1 was the only one associated with positive effect of maternal serum 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. The importance of adequate intake of vitamin E from source foods to maintain satisfactory serum vitamin and milk levels is important, as well as a better efficacy of supplementation with 800 IU of alphatocopherol. This clinical trial was recorded at http://www.ensaiosclinicos.gov.br/rg/RBR38nfg2/ (RBR-38nfg2).