Breastmilk is a truly amazing substance. Not just a nutritionally complete food, breastmilk has many complex properties. It protects babies from illness, establishes healthy gut flora and even changes flavour according to a woman’s diet. For those who can and choose to breastfeed, it has everything a bub needs at the start of life, and as more is discovered about breastmilk, formula manufacturers have a better understanding about how to make a comparable substitute.
Breast milk is always changing. In the first days after birth the baby feeds on colostrum, a yellowish liquid that is low in fat and high in easily digestible carbohydrates and proteins. Once mature milk has been established, its properties can change within a single feed. The milk’s fat content increases as the feed progresses, as fat that has collected in the milk ducts is forced into the milk as the breast empties (referred to as ‘foremilk’ and ‘hindmilk’). Hormones in breastmilk also change throughout the day. Helpfully, night milk contains hormones that help promote sleep.
Milk composition changes over longer periods of time too. Studies have found that human milk made in the second postpartum year contains higher levels of fat, protein and immune factors like lactoferrin, as toddlers feed fewer times in a day. A 2002 study of Kenyan toddlers found that breast milk still provided on average 32 per cent of a child’s energy intake and a significant portion of required vitamin A.
One 2002 study of Kenyan toddlers found that breast milk still provided on average 32 per cent of a child’s energy intake and a significant portion of required vitamin A.
It’s a prebiotic
Breastmilk contains prebiotics, non-digestible carbohydrates that are essential for healthy gut flora. Human milk contains at least 150 types of oligosaccharides, which arrive undigested in the colon where they feed good bacteria found in the gut. These friendly bacteria help strengthen the immune system and improve digestion, which is why prebiotics are now added to infant formula.
Breastmilk is also a probiotic, containing up to 700 types of bacteria at last count. Its positive effects on the microbiome could help explain why breastfeeding is associated with lower incidences of illnesses like diarrhoea when a baby is young, and a lower incidence of inflammatory bowel diseases, type 2 diabetes and obesity later in life.
It may help in the fight against superbugs
Antibiotic resistance is one of the most serious risks humans face in the 21st century, as superbugs threaten to spread unchecked around the world. Researchers at the National Physical Laboratory (NPL) and University College London have identified a miniscule fragment of the lactoferrin protein, present in breastmilk, which targets and kills pathogens like bacteria and viruses. The next step for scientists is to use this discovery to develop a lactoferrin-derived antibiotic that could be used to fight superbugs.
Studies have shown flavours like caraway, vanilla and mint can be detected by a baby in its mother’s milk up to 8 hours after consumption.
It changes flavour
Not only does the flavour of human milk change from woman to woman, its taste can change according to her diet. Studies have shown flavours like caraway, vanilla and mint can be detected by a baby in its mother’s milk up to 8 hours after consumption, while a study carried out in the seventies found that the milk of a woman who had recently eaten spicy food tasted “peppery”. This early exposure to a range of different flavours can help prepare a baby to eat a variety of foods once they start on solids. What’s more, food preferences also contribute to the creation of cultural identity. We are more likely to eat and enjoy the same foods as our mother if we develop a preference for them as newborns.
Protects against illness
There are a number of ways breastfeeding can help protect a baby from illness. One form of defence comes from the physical connection created between a woman and a baby during breastfeeding. When a baby sucks her mother’s nipple, she creates a vacuum that allows her saliva to travel into the mammary glands, which then elicits a response from the mother’s immune system. Antibodies are manufactured and sent back to the baby via the breast milk, which is now a medicine, not just a food.
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