An Exclusive Human Milk Diet Improves Premature Infant Gut Health and Feeding Tolerance

Updated: Dec 7, 2020

Exclusive human milk diet is mother's milk or donor milk

Feeding premature infants an exclusive human milk diet offers unique support to the developing gut, which is considered by many to be a second “brain” of the body. Human milk provides protection against illness, disease, and infection by delivering specific bioactive components.

An exclusive human milk diet has been shown to significantly delay or prevent necrotizing enterocolitis (NEC) when compared to traditional bovine-based artificial milk or bovine-based fortifier.1 NEC is a devastating gut disease with a 10 – 50% mortality rate,2 and quite tragically has poor outcomes once surgery is required.3

These are some of the many reasons neonatal intensive care units (NICUs) encourage mother’s own milk (MOM) as much as possible to deliver the greatest benefits from exclusive elements of a mother’s breast milk.

But what happens when a mother cannot provide breast milk, chooses not to, or has a limited supply? NICU clinicians know an exclusive human milk diet will offer those protective elements to at-risk infants in their care. They turn to donor human milk (DHM) to continue providing it.

Does an exclusive human milk diet include donor milk?

An exclusive human milk diet can consist of:

  • 100% mother’s own milk

  • A combination of mother’s own milk and donor human milk

  • 100% donor milk

The American Academy of Pediatrics (AAP) recommends an exclusive human milk diet to reduce occurrence of NEC, sepsis, and mortality. The gut may be the elusive link as to why an exclusive human milk diet works so well.

Breast milk and donor milk improve gut health

Science continues to demonstrate the relationship between the gut and overall health, including for infants. Especially true for preterm infants, the microbial dynamics in early gut microbiota can precede disease such as NEC.

Human milk contains “bioactive compounds such oligosaccharides, cytokines, immunoglobulins, microbes, and proteins among others that directly influence the developing infant and shape the intestinal microbiota colonization.”4 These bioactive compounds also help to prevent disease and stimulate gut maturation.

Parra-Llorca et al explored donor human milk having the same positive impact as mother’s own milk. They hypothesized a donor milk diet would result in a similar microbiota profile so common to preterm infants who were fed mother’s own milk.

While differences were indeed found, the results were similar enough to mother’s own milk feeding. They found minor differences between mother’s own milk and donor human milk functional profiles. Those minor differences implicated that donor milk could mimic the microbiome functionality of mother’s own milk feeding.4

Breast milk and donor milk improve feeding tolerance

Premature infants struggle with feeding tolerance. Mother’s own milk typically improves tolerance5 and enables enteral feeds sooner. Establishing enteral feeding for premature infants sooner reduces the need for parenteral nutrition. That in turn aids in minimizing central venous catheter infections.

How about for donor milk?

Quitadamo et al researched preterm infants who were fed an exclusive human milk diet, and how it impacted their feeding tolerance. They found that donor milk is “a valid substitute if taken before OMM (own mother’s milk) or in case of lack, because it holds the protective capacity against the NEC and the feeding tolerance is not statistically different compared to the OMM.”5

Donor milk also improved feeding tolerance over bovine-based artificial milk, making it a benefit to support low volume or lack of mother’s own milk when feeding preterm infants. In fact, researchers Quigley and McGuire found that formula-fed infants had a statistically significant “higher incidence of feeding intolerance compared to the donor breast milk group.”6

Exclusive human milk feeding as a priority

Human milk, whether in the form of mother’s own milk or donor milk, has a vast positive impact on the most vulnerable infants. This is especially true when feeding an exclusive human milk diet.

Encouraging mothers to either pump breast milk, or breastfeed, and working with reliable human milk nutrition resources for donor milk can aid a NICU in efforts to provide more consistent exclusive human milk feedings to their most at-risk infants. Human milk feeding should be a priority to improve outcomes for this most vulnerable patient population.

Why NICUs don't get enough donor milk

Looking for more on this subject? Read 4 Reasons NICUs Don’t Get Enough Donor Milk (and How to Fix It)

Learn more about the Benefit human milk-based nutrition line for NICU infants.


1. Herrmann, K. and Carroll, K (2014). An exclusively human milk diet reduces necrotizing enterocolitis. Breastfeeding Medicine. May 1; 9(4): 184–190. Accessed online November 17, 2020.

2. Sharma, R and Hudak, ML (2013). A clinical perspective of necrotizing enterocolitis-past, present, and future. Clinical Perinatology 40-27-51.

3. Bode, Lars (2018). Human Milk Oligosaccharides in the Prevention of Necrotizing Enterocolitis: A Journey From in vitro and in vivo Models to Mother-Infant Cohort Studies. Frontiers in Pediatrics. Accessed online November 17, 2020

4. Parra-Lorca, et al (2018). Preterm gut microbiome depending on feeding type: Significance of donor human milk. Frontiers in Microbiology, 27 June 2018, Accessed online November 16, 2020.

5. Quitadomo et al (2020). Tolerance in preterm infants fed exclusively human milk. Prospective analytic study. Nursing and Health Care (ISSN: 2573-3877). Accessed online November 16, 2020.

6. Quigley M, McGuire W (2014). Formula versus donor breast milk for feeding preterm or low birth weight infants. Cochrane Database of Systematic Reviews 2014, Issue 4. Art. No.: CD002971. DOI: 10.1002/14651858.CD002971.pub3. Accessed online November 17, 2020.