Infant nutrition: Milk polar lipids are key for healthy development

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Milk polar lipids are known for building biological membranes in the human body.¹ This class of lipids, which includes glycerophospholipids (GPL), gangliosides, and sphingophospholipids (SPH), comprises a small portion of the total milk lipids. One cannot undermine the critical role of milk polar lipids in improving cognition, endurance, physical performance, and immunity during early life.

Human milk, the gold standard in infant nutrition, serves a healthy dose of these vital lipids. When breastfeeding is impossible for various reasons, infants must rely on milk formulas for sustenance. But can infant formula supply the beneficial lipids vital for healthy development? Is there a way to develop a formula with a lipid profile mimicking breast milk?

Arun Kedia

The composition and fatty acid profile of bovine (cow) milk is vastly different from that of human milk. Sourcing the formula from bovine milk and fortifying it with highly concentrated polar lipids can bridge the gap. Bovine milk can be processed into different fractions like milk polar lipids and other milk fat globule membrane (MFGM) components. MFGM, a milk tri-layer comprising a mix of polar lipids, glycolipids, and proteins, can be further concentrated. Studies have shown that these ingredients can be used to increase the nutritional content of the infant formula.⁵ Unsurprisingly, polar lipids from bovine milk are gaining importance in human nutrition.

Milk Polar Lipids in Nutrition Formulas Can Be Beneficial for Human Health

Research shows that phosphatidylcholine (PC) and phosphatidylethanolamine (PE) are the most abundant polar lipid species in bovine milk.¹ Bovine dairy is also high in glycerophospholipids like phosphatidylserine, gangliosides, and sphingophospholipids like sphingomyelin.¹ In addition to these polar lipids, bovine milk also contains glycolipids, a component of milk known to have antipathogenic properties.² Combining dairy fat with plant oils makes it possible to develop a lipid profile in formula closer to breast milk regarding fatty acid composition, triglyceride structure, polar lipids, and cholesterol content.⁴ Such a formula is significantly better than formulas that use lipids sourced from plants.

Polar lipid preparations from bovine milk also contain cholesterol. Cholesterol, which is already a part of the MFGM structure, is known to be a building block of cell membranes as well as a precursor for vitamin D and is essential for infants. Studies suggest that dietary cholesterol plays a role in the cortical composition of the brain and influences behavior.¹ It also helps synthesize bile acids, lipoproteins, lipophilic vitamins, and steroid hormones.¹

Milk polar lipid preparations, mainly MFGM ingredients, have been central to nutrition research. They are studied primarily for their role in enhancing the efficacy of infant nutrition formula.¹ One study showed that infant formula with MFGM-enriched whey increased serum cholesterol concentrations and narrowed the gap between formula-fed and breastfed infants.¹ Another study showed that infants fed with MFGM-enriched formula had a lower incidence of otitis media compared with those fed a non-enriched formula, a detail which may be clinically significant.¹

As per a study, a feeding formula enriched with milk polar lipids containing gangliosides showed improved hand and eye coordination, performance IQ, and general IQ in infants compared to a non-enriched formula.¹ Milk polar lipid preparations thus may be beneficial in aiding neurocognitive development and brain structure in infants.^3,8

Studies have also shown that MFGM-enriched whey protein helped reduce the prevalence of diarrhea compared to normal skim milk proteins.¹ When combined with lactoferrin, a formula enriched with MFGM reduced respiratory-associated adverse events. All this demonstrates a beneficial effect for milk polar lipids against infections or infection-associated complications.¹

Milk polar lipids have beneficial nutritional properties. However, one of the challenges is that the native MFGM lipid globule structure and overall composition are affected during processing. This is why academicians and industrialists are investing in improving the technology and processes for purifying and concentrating them. Buttermilk and butter serum are sources of MFGM fragments and milk polar lipids.⁷ Bovine milk–derived ingredients, including whey and cream, are used as MFGM-enriched sources to supplement milk polar lipids in food products.

More Research Is Needed to Establish Safety

While one of the significant applications of bovine milk polar lipidsremains infant nutrition¹, one might wonder just how safe these ingredients are.

Studies have shown that enriching a formula with bovine milk–derived MFGM results in healthy growth compared to standard formula. Other dedicated studies in infants and adults demonstrate the growth and safety of milk polar lipids in different applications.¹ For example, a study in the Dutch Trial Register reported that an infant formula with large, milk phospholipid–coated lipid droplets containing dairy lipids was safe and well tolerated and supported adequate growth in healthy infants.⁶ While milk polar lipids may be safe to use, more research is needed to confirm the effect of higher doses on humans.

Future of Milk Polar Lipids in Infant Nutrition

The growing need for infant feeding alternatives makes it even more important to assess the merits of feeding using infant formula, especially given the implications of lifelong immunity and the child’s health. Regulating and monitoring the infant formula market is gaining momentum, especially in developing nations. There is an opportunity here to promote research on milk polar lipids in increasing the nutritional efficiency of infant formulas.

Studying the structure and functionality of milk polar lipids makes for an exciting research topic. Insights into the role of polar lipids in lipid digestion and absorption can be applied to develop innovations in infant nutrition. An infant formula with a polar lipid profile similar to human milk will have significant commercial advantages.

One cannot ignore the growing demand for such products and the impact on the lives of infants that depend on them. For this reason, the onus lies on infant formula manufacturers to pursue newer ways of improving their products’ nutritional and immunity benefits. The scientific community and industry may have learned much about milk polar lipids; however, there is still a lot to be discovered. For this reason, academicians and the industry must continue to invest in research to fully unlock the potential of milk polar lipids.

About the Author

Arun Kedia is the managing director of VAV Lipids, (Mumbai, India), an innovation-driven company specializing in cGMP-grade manufacturing of lecithin and phospholipids for nutraceutical, pharmaceutical, and cosmeceutical applications. For more information, please visit http://www.vav.in or e-mail marketing@vav.in.

References

1. Venkat, M.; Chia, L.W.; Lambers, T.T. Milk polar lipids composition and functionality: A systematic review. Crit Rev Food Sci Nutr. Published online August 23, 2022. DOI: 10.1080/10408398.2022.2104211
2. Peterson, R.; Cheah, W.Y.; Grinyer, J.; Packer, N. Glycoconjugates in human milk: Protecting infants from disease. Glycobiology. 2013, 23 (12), 1425–1438. DOI: 10.1093/glycob/cwt072
3. Nieto-Ruiz, A.; García-Santos, J.A.; Verdejo-Romá, J.; et al. Infant formula supplemented with milk fat globule membrane, long-chain polyunsaturated fatty acids, and synbiotics is associated with neurocognitive function and brain structure of healthy children aged 6 years: The COGNIS study. Front Nutr. Published online March 9, 2022. DOI: 10.3389/fnut.2022.820224
4. Gianni, M.L.; Roggero, P.; Baudry, C.; et al. An infant formula containing dairy lipids increased red blood cell membrane omega 3 fatty acids in 4 month-old healthy newborns: A randomized controlled trial. BMC Pediatr. 2018, 18 (1), 53. DOI: 10.1186/s12887-018-1047-5
5. Moloney, C.; O’Conner, D.; O’Regan, J. Polar lipid, ganglioside and cholesterol contents of infant formulae and growing up milks produced with an alpha lactalbumin-enriched whey protein concentrate. Int Dairy J. 2020, 107. DOI: 10.1016/j.idairyj.2020.104716
6. Breij, L.M.; Abrahamse-Berkeveld, M.; Vandenplas, Y.; et al. An infant formula with large, milk phospholipid–coated lipid droplets containing a mixture of dairy and vegetable lipids supports adequate growth and is well tolerated in healthy, term infants. Am J Clin Nutr. 2019, 109 (3), 586–596. DOI: 10.1093/ajcn/nqy322
7. Lopez, C.; Cauty, C.; Guyomarc’h, F. Organization of lipids in milks, infant milk formulas and various dairy products: Role of technological processes and potential impacts. Dairy Sci Technol. 2015, 95 (6), 863-893. DOI: 10.1007/s13594-015-0263-0
8. Pawar, A.; Zabetakis, I.; Gavankar, T.; Lordan, R. Milk polar lipids: Untapped potential for pharmaceuticals and nutraceuticals. PharmaNutrition. 2023, 24. DOI: 10.1016/j.phanu.2023.100335