Should human milk products be homogenised? Experts weigh in

Manufacturing processes for human milk-based products vary widely, which may influence the composition of the products. One such extensively used manufacturing process – homogenisation, with or without heat – alters the evolutionarily evolved structure of human milk’s bioactive components. The safety and efficacy of homogenised human milk-based nutritional products are yet to be established.

When infants are born prematurely, feeding them can be a daunting challenge. Not only do these babies have intensive nutritional needs to help the brain and lungs prepare for life outside the womb, but they are also often extremely medically fragile.¹

Neonatologists face a conundrum: The American Academy of Pediatrics recommends that infants be fed exclusively with breast milk during the first six months of life due to evidence of both short- and long-term medical and neurodevelopmental advantages associated with exclusive human milk diets.² Breast milk alone, however, can’t provide enough nutrition to make up for what premature infants would have received in the final weeks of pregnancy if they had not been born prematurely.³

Premature infants require fortifiers to be added to breast milk to provide the intensive nutrition needed to support healthy growth and development.² Both baby formula and nutritional fortifiers used in the NICU have long been made from cow’s milk, which has been associated with an increased risk of serious, life-threatening complications.⁴

Fortunately, human milk-based fortifiers are becoming the standard of care in the world’s top level III and IV NICUs. Prolacta Bioscience (Duarte, CA) has been a market pioneer, developing high-quality products and delivering the first-ever 100 percent human milk-based fortifiers to NICUs since 2007. These well-studied products have never been homogenised. Compared to feeding cow milk-based products, Prolacta’s products, when used as part of an Exclusive Human Milk Diet (EHMD), have been clinically proven in 20+ peer-reviewed studies to:

• Lower mortality and morbidity^4-7
• Reduce incidence of feeding intolerance⁶
• Achieve adequate growth^4,8-11
• Reduce incidence of bronchopulmonary dysplasia (BPD)^5,6,8,12
• Reduce incidence of retinopathy of prematurity (ROP)^5,6,12,13
• Reduce late-onset sepsis incidence and evaluations^5,12,13
• Reduce risk of necrotising enterocolitis (NEC)^4,5,6,14
• Improve long-term outcomes such as body composition, insulin resistance, and neurodevelopment^15-17
• Shorten stays in the NICU⁶
• Reduce hospital costs.^6,18,19

What makes human milk the perfect nutrition for premature infants?

Human milk is a complex, dynamic bioactive fluid with a myriad of compounds that support immature infants’ overall growth, immune system, neurodevelopment, and overall long-term health.²⁰

The major difference between cow milk-based and human milk-based products is the bioactive components that are unique to human milk.^21,22 Bioactive components in human milk include proteins such as immunoglobulins, lactoferrin, lysozyme, and the wide spectrum of prebiotics known as human milk oligosaccharides (HMOs), which are not easily manufactured and thus are minimally present or missing from cow milk-based nutritional products.²³

Milk fat globule membranes (MFGMs) are additional important bioactive components of human milk. These molecules improve infants’ immune defense and reduce inflammation.²¹ They also improve gut function, even as they reduce the risk of infections.²⁴ MFGMs support different aspects of infants’ development, including their microbiome, metabolism and neurodevelopment.²⁴

Human milk: handle with care

Prolacta’s 100 percent human milk-based nutritional products have the highest bioactivity in the human milk industry.²⁵ Prolacta’s nutritional products are vat pasteurised using processes defined by the US Food and Drug Administration’s (FDA) pasteurised milk ordinance to ensure that any pathogens are inactivated while retaining as much of the milk’s natural bioactivity as possible.³ Well-studied and currently available human milk-based products are not homogenised.

As other manufacturers begin to enter the human milk-based fortifier arena, some are employing a variety of processing methods such as retort sterilisation and ultra-high-temperature (UHT) processing and are homogenised. The effects of such processes on the human milk products given to premature infants is completely unknown. We need to better understand the impact of these different processing methods on the composition and bioactivity of breast milk.

Homogenisation is a process that evenly disperses two liquids to create a single uniform mixture. In the dairy industry, homogenisation is used to improve cow milk’s taste, consistency and appearance, as well as to extend its shelf life. Manufacturers homogenise cow milk to disperse fat droplets and prevent the cream from rising to the top.

Remarkably, some newer human milk companies are routinely using homogenisation, even though there is no clinical evidence on the safety and efficacy of using homogenised human milk products in the premature infant population. Homogenisation is not a common practice for established milk banks, which collect and store donated breast milk, or companies currently producing human milk-based products.

Manufacturing matters

We recently authored a peer-reviewed perspective that summarises existing evidence on the impact of homogenisation on human milk-based nutritional products.²⁶ The article focuses on changes to the macromolecular structure of the milk fat globule (MFG) and the subsequent impact on digestion. We used published data to create a conceptual framework for the potential implications of homogenised human milk-based nutritional products on preterm infant health and suggest avenues for future research.

Among our conclusions: Homogenisation disrupts the MFGM, which may lead to premature digestion of bioactive components, including sphingolipids and long-chain polyunsaturated fatty acids (LCPUFAs). Adequate intake of these components has been linked to favorable neurological outcomes.²⁷ We have no clinical data on the effects of changes to the MFG and its membrane and do not know the implications of these changes for infant health.

Furthermore, the well-established clinical benefits of human milk-based nutritional products apply only to currently available non-homogenised products. The safety and efficacy of homogenised human milk products is unknown, and there is no clinical data supporting the use of homogenised human milk-based products in premature or other critically ill infants.

Human milk-based nutritional products are not created equal. As human milk researchers and medical professionals, it is our opinion that the use of industrial processing techniques such as homogenisation, with or without high-heat processing, should be avoided for human milk-based nutritional products until their safety and efficacy have been established. Potentially disrupting the natural MFG and its membrane with homogenisation is not our current recommendation based on the information available.

References

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25. Data on file.
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