The Reference Intervals of Whole Blood Copper, Zinc, Calcium, Magnesium, and Iron in Infants Under 1 Year Old.

Trace elements are essential nutrients for the optimal growth, development, and health of infants, and the reference intervals (RIs) from these trace elements in the blood are very important for an accurate assessment of the status of the elements. In this study, blood samples from a total of 13,446 infants (7206 boys and 6240 girls) were used, and the copper (Cu), zinc (Zn), calcium (Ca), magnesium (Mg), and iron (Fe) in their blood were determined using atomic absorption spectrometry. After clearing the data and removing any outliers, the gender- and age-specific RIs obtained from the Cu, Zn, Ca, Mg, and Fe in the infants' blood were established according to the principles of the Clinical and Laboratory Standards Institute (CLSI) C28-A3. In the multivariable analysis, after making the relevant adjustments for the confounding factors, the age of the infants showed a significant positive correlation with the concentrations of Zn, Ca, Mg, and Fe found in the blood (p<0.01). Furthermore, there were obvious differences in the Cu, Zn, and Ca levels in the blood according to the gender of the infants (p<0.01). As infants are in the critical period of their growth and development, the gender- and age-specific RIs may provide helpful guidance for the nutritional status of the Cu, Zn, Ca, Mg, and Fe elements in the infants' blood.