Premature Infants have Lower Gastric Digestion Capacity for Human Milk Proteins than Term Infants

Veronique Demers-Mathieu, Yunyao Qu, Mark Underwood, Robyn Borghese, David Charles Dallas

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Objectives: Whether premature infants have lower gastric protein digestive capacity than term infants and the extent to which human milk proteases contribute to overall gastric digestion are unknown and were investigated in this study. Methods: Human milk and infant gastric samples were collected from 16 preterm (24-32 wk gestational age) and 6 term (38-40 wk gestational age) mother-infant pairs within a range of 5 to 42 days postnatal age. For each pair, an aliquot of human milk was adjusted to pH 4.5 and incubated for 2 hours at 37 °C to simulate the gastric conditions without pepsin (milk inc). Their gastric protein digestion capacity was measured as proteolysis (free N-terminals) and protease activities. Two-way analysis of variance followed by Tukey post hoc test was applied to compare measurements between preterm and term infants as well as among human milk, milk inc, and gastric samples. Results: Measurements of gastric protein digestion were significantly lower in preterm infants than term infants. Overall milk protease activity did not differ between human milk samples from term- and preterm-delivering mothers. As protease activity did not increase with simulated gastric incubation, milk proteases likely contributed minimally to gastric digestion. Conclusions: Preterm infants have lower gastric protein digestion capacity than term infants, which could impair nutrient acquisition. Human milk proteases contribute minimally to overall gastric digestion. The limited activity of milk proteases suggests that these enzymes cannot compensate for the premature infant's overall lower gastric protein digestion.

Original languageEnglish (US)
Pages (from-to)816-821
Number of pages6
JournalJournal of Pediatric Gastroenterology and Nutrition
Issue number5
StatePublished - May 1 2018


  • enzyme
  • gastric acid
  • postnatal age
  • preterm milk
  • Term milk

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Gastroenterology


Dive into the research topics of 'Premature Infants have Lower Gastric Digestion Capacity for Human Milk Proteins than Term Infants'. Together they form a unique fingerprint.

Cite this