Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency.

Abstract

As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine -mean (SEM) 10 (1) ,ug/dl -than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30

Neonatal Hypothyroxinemia: Effects of Iodine Intake and Premature Birth

“…This does not mean that parameters of thyroid function are not ameliorated by increasing the I intake of PT babies, as their circulating T 3 , FT 4 , Tg, and TSH levels are improved with higher I intakes independently of PMA, as apparent from Table 2 and in agreement with our previous report (14) in which I intake of PT neonates above or below 40 g I/day was used as the qualitative condition separating the data for covariance analysis.…”

“…On each occasion, samples of the different formulas or maternal milk given to each baby were kept for the direct determination of I content, and the ingested volume over a 24-h period was recorded in each case, as described previously in more detail (14). The 24-h urine was collected at each study period for the determination of I and creatinine concentrations.…”

“…The I intake is calculated from the I concentration of the formula or maternal milk, which we have previously reported in detail (14), and the volume ingested.…”

“…In a previous study (14) we determined the I content of breast milk, 32 formulas from different brands used in Spain, and 127 formulas from 14 other countries. Breast milk contained more I (10 Ϯ 1 g I/dL) than the majority of formulas, especially those for premature infants.…”

“…This lead us to investigate the I content of formula preparations used for premature infants and for T neonates (14). The present study investigates the role of I intake on the thyroid function of PT infants.…”