Trace elements

Magnus Domellöf introduces this step and the key learning points for trace elements in preterm nutrition.

The transcript for this audio can be found here or in the downloads section below.

Trace elements are essential for normal growth and organ function.

Adequate dietary intake of trace elements is important for preterm infants to prevent deficiencies, but excessive intake can result in adverse effects. The key functions of the trace elements above, as well as the potential impact of insufficient or excessive intakes, are summarised in the table below:

If you require a screen-reader compatible version this is available as a PDF.

Iron

Systematic reviews show that iron supplements effectively prevent iron deficiency anemia in preterm infants. There is no benefit of exceeding the standard iron dose (i.e., 2-3 mg/kg/day) unless the baby is receiving erythropoietin in order to reduce the need for blood transfusions.

In late preterm infants, iron supplementation showed improved developmental outcomes. However, there is a lack of randomised controlled trial data with long-term neuro-developmental outcomes in very preterm infants. Earlier iron supplementation (2-3 weeks compared to 4-8 weeks) results in a lower requirement for preterm infant blood transfusions.

300-350 micrograms/L,’ on the lighter side is ‘deficiency,

Recommendations

If you require a screen-reader compatible version this is available as a PDF.

Zinc

Zinc is an essential trace element involved in growth and tissue differentiation.

Zinc deficiency in preterm infants is associated with the following problems:

Unlike iron and copper, zinc does not have a pro-oxidant effect.

Adverse effects of excess zinc intakes are rarely reported, except for a negative effect on copper absorption with high zinc intakes.

Data from factorial methods combined with metabolic balance studies suggest enteral zinc intakes of at least 2.0-2.25 mg/kg/day are required, and up to 3 mg/kg/day may be needed in extremely preterm infants due to faster growth rates.

Recommendations

If you require a screen-reader compatible version this is available as a PDF.

Other trace elements

Recommendations also exist for copper, selenium, manganese, iodine, chromium, and molybdenum:

• The recommended copper intake has been increased to compensate for the higher recommended zinc intake (see above), since these two ions compete for intestinal absorption.
• The recommended selenium intake results in selenium status like term infants and possibly a reduced risk of sepsis.
• The recommended manganese intake is based on the average human milk manganese content and the lower range of manganese in current preterm formulas.
• Intakes of iodine, chromium and molybdenum remain unchanged.

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