Correlation of vitamin A nutritional status on alpha-tocopherol in the colostrum of lactating women

The adequate supply of vitamins A and E to newborns is essential. However, factors such as maternal nutritional status and nutrient interaction may limit its bioavailability. The aim of this study was to establish nutritional status for vitamins A and E and evaluate the correlation of retinol on colostrum alpha-tocopherol in lactating women. A total of 103 lactating women were recruited at a Brazilian public maternity hospital. Fasting serum and colostrum samples were collected in the immediate post-partum. Retinol and alpha-tocopherol levels were determined by high-performance liquid chromatography and nutritional status for these vitamins was defined from specific cut-off points for serum and colostrum. Mean serum and colostrum retinol (1.49 mu mol L-1, 2.18 mu mol L-1) and alpha-tocopherol (26.4 mu mol L-1, 26.1 mu mol L-1) indicated satisfactory biochemical status. However, we found a prevalence of subclinical deficiency of vitamin A and vitamin E in serum (15.5% and 16%) and colostrum (50% and 60%). Lactating women with serum retinol = 1.05 mu mol L-1 showed an inverse correlation between serum retinol and alpha-tocopherol concentration in the colostrum (P = 0.008, r = -0.28). This association was not observed in serum level < 1.05 mu mol L-1. The nutritional status of lactating women for vitamins A and E was adequate, although there is a risk of subclinical deficiency. The negative correlation of serum retinol on alpha-tocopherol concentration in the colostrum must be carefully evaluated in situations of vitamin A supplementation, because alpha-tocopherol bioavailability in maternal milk may be compromised.