Longitudinal Study on Trace Mineral Compositions (Selenium, Zinc, Copper, Manganese) in Korean Human Preterm Milk

Abstract

We measured selenium, zinc, copper and manganese concentrations in the human milk of Korean mothers who gave birth to preterm infants, and compared these measurements with the recommended daily intakes. The samples of human milk were collected postpartum at week-1, -2, -4, -6, -8, and -12, from 67 mothers who gave birth to preterm infants (< 34 weeks, or birth weight < 1.8 kg). All samples were analyzed using atomic absorption spectrophotometry. The concentrations of selenium were 11.8 ± 0.5, 11.4 ± 0.8, 12.7 ± 0.9, 11.4 ± 0.8, 10.8 ± 0.9, and 10.5 ± 1.3 µg/L, zinc were 7.8 ± 0.5, 9.1 ± 0.8, 7.2 ± 0.9, 8.0 ± 0.8, 7.4 ± 0.9, and 6.6 ± 1.2 mg/L, copper were 506 ± 23.6, 489 ± 29.4, 384 ± 33.6, 356 ± 32.9, 303 ± 35.0, and 301 ± 48.0 µg/L and manganese were 133 ± 4.0, 127 ± 6.0, 125 ± 6.0, 123 ± 6.0, 127 ± 6.0, and 108 ± 9.0 µg/L at week-1, -2, -4, -6, -8, and -12, respectively. The concentrations of selenium and zinc meet the daily requirements but that of copper is low and of manganese exceeds daily requirements recommended by the American Academy of Pediatrics, Committee on Nutrition.

Increased early enteral zinc intake improves weight gain in hospitalised preterm infants

“…Finally, for each infant, we used a single feeding sample at two weeks of life as a marker for early Zn intake rather than obtaining serial samples throughout hospitalisation. However, the Zn concentration of preterm breast milk has been shown to be relatively stable during the first 12 weeks of lactation . Furthermore, the present study focused on the effect of early enteral Zn intake on growth outcomes of preterm infants; thus, the contribution of the natural decline in breast milk zinc concentration should be small.…”

Trace Elements in the Human Milk

“…In adulthood, copper deficiency is associated with hypochromic anemia, neutropenia, hypopigmentation, deficient bone formation with osteoporosis, and vascular deficiencies [7]. The deficiency of this element in the infant is related to identical symptoms [7,14]. Copper is mainly accumulated in the liver, especially during the third trimester of pregnancy.…”

“…Copper is mainly accumulated in the liver, especially during the third trimester of pregnancy. Premature infants tend to have lower copper stores compared to full-term children [14]. There is a decrease in copper concentration in milk during lactation, reaching a minimum of 0.08-0.10 mg/L in mature milk between 6 months and 1 year [15].…”

“…Although there are symptoms associated with manganese deficiency, it was not possible to clearly establish a relationship between low dietary intakes and health problems. Manganese toxicity causes central nervous system effects similar to those of Parkinson's disease [14,22]. In one study in Japanese women, the concentrations of manganese in breast milk showed a very low variability throughout the lactation period [9].…”

Atomic spectrometry update. Clinical and biological materials, foods and beverages

“…The nutritional suitability of human milk produced by mothers of preterm infants in terms of Cu, Mn, Se and Zn was studied where infants were born <34 weeks or with a body weight <1.8 kg. 143 Although Mn exceeded daily requirements suggested by the American Academy of Paediatrics and Cu was below, both concentrations increased the closer the birth was to term. Concentrations of Se and Zn met daily requirements regardless of length of the pre-term period.…”