What is in breast milk? That’s a question that has intrigued researchers for decades. After all, breast milk a highly complex recipe for nutrition, differing depending on a mom’s ethnic background, where she lives, even what she eats. To study breast milk, researchers have typically collected samples from mothers in their geographic area. But this local focus doesn’t capture the true diversity of breast milk, and comparing samples between these banks is impossible because they were collected and stored differently.
Now researchers have a more advanced resource: the Global Exploration of Human Milk (GEHM), the first international study of its kind, based on approximately 1,500 samples of breast milk from around the globe. The GEHM Study is a collaborative effort between Mead Johnson Nutrition and top medical institutions, a global leader in human milk studies1,2,3,4, in Cincinnati, Mexico City, and Shanghai.
Researchers for the GEHM collected breast milk from 120 pairs of mothers and infants in each of three countries—Mexico, China, and the United States—over the course of two years of breast-feeding. Nearly 1,500 unique samples of breast milk were collected2,3, bar-coded with a very sophisticated system, and stored under strict scientific conditions3. Look at mothers that have distinct genetic, geographic and dietary patterns.
GEHM researchers tracked the growth of the infant, any changes in the mother’s weight, how often the infant breast-fed, and when the baby started receiving solid food. In addition, they tracked the baby’s health, allergies, and sun exposure2,3. It’s designed to serve as a unique resource to study how breast milk composition changes as a baby develops, how it differs among populations and is dependent on where the mother lives, and how those differences are related to infant development1,2,3,4.
We know how human milk changes over the course of lactation and how variable it is between mothers. We have a leading edge appreciation for what aspects of human milk are consistent and which are likely to be variable. We understand the cultural differences in complimentary feeding and how this affects overall feeding of infants. We can study how human milk is designed for toddlers. Identifying important nutrients and compounds in breast milk has been an important outcome of GEHM, but just as important has been discovering the levels of these nutrients in breast milk.
The GEHM allows researchers to not only improve their understanding of the nutrients that make up breast milk but the function of each nutrient and how it changes over time. To do this, they use cutting-edge technology called “cellnomics” to study the more than 1,000 proteins that compose breast milk. With this technology, they can observe how live intestinal cells respond to the milk at the molecular and genetic levels2.
GEHM, along with other studies of breast milk, has enabled researchers to optimize nutrient levels in our infant formula, even taking into account regional differences. “For instance, women on the coast of China eat a lot of fish before and after birth,” says Robert McMahon, PhD, director of global discovery and analytical sciences at Mead Johnson Nutrition. “That translates into very high levels of docosahexaenoic acid (DHA), a fatty acid found in some fish and important for healthy brain and vision development. But in the southwest United States, where there is little fish consumption, women have lower levels of DHA6,7,8.” This global view helps Mead Johnson scientists target the nutrient levels present in breast milk, which will provide the most benefit for the most babies across populations5,7,8.
We have mapped over 1500 human milk proteins. Unique model of a baby’s digestion shows us how the baby digests human milk nutrients in order to absorb them. High tech “proteomics” method means we can diagnose what benefits the proteins provide and how those benefits change over time. So we have researched and understand the importance of lactoferrin and MFGM. We go beyond knowing the right levels of lactoferrin. We also know how your baby’s body uses lactoferrin and how it functions. So, we can specify the best type of lactoferrin to be absorbed by a baby’s body.
Docosahexaenoic and arachidonic acid concentrations in human breast milk worldwide. American Journal of Clinical Nutrition 2007 Jun; 85(6):1457-64