2021 Volume 57 Issue 2 Pages 295-300
In Japan, large quantities of iodone-rich food are commonly consumed. Excessive iodine Intake in newborn period is harmful effect to thyroid function. However, there are few reports about an amount of iodine intake of the low-birth-weight infants. The aim of this study was to measure an amount of iodine discharge, and presume an amount of iodine intake of the low-birth-weight infant. We enrolled 37 low-birth-weight infants which could use enteral nutrition sufficiency were measured. Iodine in the urine was measured at the time of thyroid function measurement, and the iodine intake was inferred from urine amount. The median of the urine iodine concentration was 300μg /L, the median of iodine intake was 43.8μg/day. 6 cases exceeded the upper limit of iodine intakes, and all of 3 cases over 1,000μg/day developed thyroid dysfunction. Breast milk is a valuable source of iodine for low-birth-weight infants, but the iodine content of breast milk varies from person to person, and in some cases, it is extremely high. It is important to understand the iodine intakes of low-birth-weight infants from the urinary iodine concentration.
