To evaluate the influence of supplementation with retinyl palmitate in the immediate postpartum period on the levels of secretory immunoglobulin A (SIgA) in colostrum.

To evaluate the effect of maternal supplementation with vitamin E on the concentration of α-tocopherol in colostrum and its supply to the newborn. This randomized clinical trial enrolled 99 healthy adult pregnant women; of these, 39 were assigned to the control group and 60 to the supplemented group. After an overnight fast, 5mL of blood and 2mL of colostrum were collected. After the first sampling (0h milk), the supplemented group received 400IU of supplementary vitamin E. Another 2mL milk aliquot was collected in both groups 24h after supplementation (24h milk). The samples were analyzed by high-performance liquid chromatography. The α-tocopherol content provided by colostrum was calculated by considering a daily intake of 396mL of milk and comparing the resulting value to the recommended daily intake for infants aged 0-6 months (4mg/day). The initial mean concentration of α-tocopherol in colostrum was 1509.3±793.7μg/dL in the control group and 1452.9±808.6μg/dL in the supplemented group. After 24h, the mean α-tocopherol concentration was 1650.6±968.7μg/dL in the control group (p>0.05) and 2346.9±1203.2μg/dL in the supplemented group (p<0.001), increasing the vitamin E supply to the newborn to 9.3mg/day. Initially, 18 women in the supplemented group provided colostrum α-tocopherol contents below 4mg/day; after supplementation only six continued to provide less than the recommended amount. Maternal vitamin E supplementation increases the supply of the vitamin to the infant by providing more than twice the Recommended Daily Intake.

Background: Vitamin E supplementation might represent an efficient strategy to increase the vitamin E content in milk. The present study aimed to evaluate the impact of supplementation with 800 IU RRR-alpha-tocopherol on the alpha-tocopherol content of milk and the factors associated with the increase in vitamin E. Methods: Randomized clinical trial with 79 lactating women from Brazil, who were assigned to the control group, or to the supplemented group (800 IU of RRR-alpha-tocopherol). Milk and serum were collected between 30 and 90 days after delivery (collection 1), and on the next day (collection 2). Alpha-tocopherol was analyzed using high-performance liquid chromatography. Results: In the supplemented group, the alpha-tocopherol content in serum and milk increased after supplementation (p < 0.001). In the multivariate analysis, only alpha-tocopherol in milk (collection 1) was associated with the level of this vitamin in milk after supplementation (β = 0.927, p < 0.001), and binary logistic regression showed that the dietary intake was the only determinant for the greater effect of supplementation in milk. Conclusion: The pre-existing vitamin level in milk and diet are determinants for the efficacy of supplementation in milk, suggesting that in populations with vitamin E deficiency, high-dose supplementation can be used to restore its level in milk.

Key words: diabetes, gestational; colostrum; serum; alpha-tocopherol

To evaluate retinol concentration in colostrum samples collected with a 24 hour interval. Colostrum was collected from 24 recently-delivered mothers at two points in time, 0 hours (T0) and 24 hours later (T24), and a pooled sample of colostrum from T0 and T24 was also analyzed. Fat content was determined by creamatocrit, and retinol assayed by high performance liquid chromatography. When expressed in terms of volume of milk (microg/dL), retinol levels varied across T0, T24 and the pooled sample: 94.9+/-58.9; 129+/-78.6 and 111.9+/-60.4 microg/dL, respectively. However, when expressed with relation to fat content (microg/g), no significant difference was observed. Retinol assayed in colostrum from a single sample should not be used as an indicator of vitamin A nutritional status, due to the great variation between samples collected at different times. It is suggested that results be expressed per gram of fat, in order to minimize variations resulting from the volume of milk.