Human milk composition: nutrients and bioactive factors

Pediatr Clin North Am. 2013 Feb;60(1):49-74. doi: 10.1016/j.pcl.2012.10.002.


This article provides an overview of the composition of human milk, its variation, and its clinical relevance. The composition of human milk is the biological norm for infant nutrition. Human milk also contains many hundreds to thousands of distinct bioactive molecules that protect against infection and inflammation and contribute to immune maturation, organ development, and healthy microbial colonization. Some of these molecules (eg, lactoferrin) are being investigated as novel therapeutic agents. Human milk changes in composition from colostrum to late lactation, within feeds, by gestational age, diurnally, and between mothers. Feeding infants with expressed human milk is increasing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Breast Milk Expression
  • Dietary Fats / metabolism
  • Dietary Proteins / metabolism
  • Female
  • Humans
  • Infant
  • Infant Nutritional Physiological Phenomena
  • Infant, Newborn
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Lactation / physiology
  • Lactose
  • Micronutrients / metabolism
  • Milk Banks
  • Milk, Human / chemistry
  • Milk, Human / immunology
  • Milk, Human / metabolism
  • Milk, Human / physiology*
  • Pasteurization


  • Dietary Fats
  • Dietary Proteins
  • Intercellular Signaling Peptides and Proteins
  • Micronutrients
  • Lactose