INFLUENCE OF DIETARY TAURINE ON VITAMIN-D ABSORPTION

To evaluate the influence of dietary taurine supplementation on vitami n D absorption, we studied three groups of infants: 21 (11 preterm) we re fed a taurine-free formula, 21 (10 preterm) were fed a taurine-supp lemented formula (50 mg/100 g of powder) and 20 (9 preterm) were fed h uman, not heat-treated milk. Taurine, total bile acids, glyco-(GBA) an d tauro-(TBA) conjugated bile acids, 25-hydroxyvitamin D3 (25OHD3) and 1,25-dihydroxyvitamin D3 (1,25OH2D3) were determined in all infants a t birth in blood cord and at one and three months of life. In preterm infants fed a taurine-free formula, we found lower plasma taurine leve ls than in infants of other groups at one and three months of life. In these infants, GBA predominated, with a G/T ratio of 1.1 and 1.4 at o ne and three months of life, whereas in all other infants TBA predomin ated with a G/T ratio always < 1. Also, 25OHD3 and 1,25OH2D3 levels we re significantly lower in preterm infants fed a taurine-free formula t han in infants fed a taurine-enriched formula or human milk. Term infa nts fed a taurine-free formula did not show differences in the paramet ers studied in comparison to infants of other groups. Low taurine diet ary intake appears to compromise vitamin D absorption in preterm infan ts, and therefore taurine supplementation of preterm infant formulas s hould be encouraged.