Early life nutrition and lifelong health: lactation science and barriers. Flashcards
LO:
This session relates to the following TILOs:
- Embryo-fetal environment: Summarise how the extrauterine environment can impact embryo and fetal development and health across the life-course.
- Child and adolescent development: Summarise the key developmental milestones of child and adolescent development and expected timeframes.
Session plan:
Is there a biological difference between breast milk and formula?
67% said no, but of course there is, formula is made from cow milk.
Does being formula-fed have long-term consequences for health?
72% said no, the answer is yes but our society don’t know this.
What are the WHO guidelines for breastfeeding?
Exclusive for around 6 months ie when they are developmentally ready-can sit up, support themselves, spoon feed etc.
What is the full duration of breastfeeding per child?
Clues in our culture-when children lose milk teeth-this is when weaning should happen.
Culturally it would be very weird to feed for 4 years.
Evolution of lactation
All mammals have the capacity to lactate (we are placental mammals)
But if compared to cow milk, you wouldn’t choose it as replacement. Cows are proboscia, high protein as they need high muscle mass to run around field
All tracks back to cynodonia-layed eggs. Those mothers that had capacity to produce fluid they would hydrate babies and it then developed antimicrobial properties so babies survived better. Then later nutritional evolution occured in the milk.
Important to protect child from pathogens now and later
The content of human milk:
- antimicrobial factors
- Human milk has high fatty acid content. Probs why brain growth is great in early humans and why we have different brain speeds that other organisms. Could be due to mutation that evolved in lactocytes
- Higher tryptophan is found later in the day. Helps to pattern the children’s sleep system. The tryptophan helps children develop a dirunal rhythm.
- Pluripotent stem cells in human milk are taken up, absorbed through the gut and are found in every organ system in the body effectively. Not yet known if this is an accident or whether they are doing something functionally to protect the infants against future insults.
Antiviral functions of HM
- Secretory IgA is the most common antibody in human milk
- Incredible diversity both of mechanisms and classes. Have multiple antiviral functions, emphasising importance of human milk in immune development.
Infant feeding and the microbiome
Infants-put everything in their mouth, as gut helps to differentiate between friend and foe. Helps them sample environment.
Breast milks helps to pattern the infant’s gut microbiome. Main way it does this is through oligosaccharides, which are short chain sugars. Human milk is unique in that it has enormous complexity around the oligosaccharides, over 200 have been described, and each mother has a unique fingerprint which is predetermind by their genetics, but also their environment, even the seasons of the year, and pathogens etc. Now 20 of those short chain sugars can’t be metabolised ie used by the infant. And the reason they are there are as metabolites for bifidobacteria and lactobacilli, and they preferentially select those bacteria to grow and reproduce.
The intestinal barrier
This is a representation of the gut epithelium, a single cell layer. In infants, there is some degree of a 2 way process, can see there are gaps between the cells that allows big molecules like immunoglobulins, stem cells even, to be taken up by the infant from the milk. But it also allows dendritic cells to poke little tendrils out into the lumen to sample the gut bacteria and proteins that are coming down, and then they chop them up and present them to T cells and B cells in the gut wall. They are able to differentiate between friend and foe.
But once infants start taking solid food, it is not great to have chunks of cucumber end up in the gut wall, so as soon as non-human protein is identified by the gut epithelium, a range of genetic signalling activate tight junctions to stop solid food getting through. However it also blunts this immune programming mechanism, which could be one reason why it drives infants towards a greater risk of autoimmune disease in later life.
Explains increasing autoimmune disease and allergy.
Macrophages, t cell, maternla antibodies traverse cells. Dendritic cells project out to sample antigens.
When infants are weened onto solid food, when non human protein contacts gut it seals up between cells, good as prevents food getting stuck here, but if baby is a day old being fed formula this isn’t good. If baby is continually formula fed then there will be blunting of immune development.
A new model of health
Aberrant microbiome
Microbiome is primarily patterned by infant feeding
If caecarian born will have different microbiome, if breast feed it can correct to normal microbiome, same as vaginal delivery microbiome
Metabolic programming
Flawed studies as breast fed (includes 3 year old who is still feeding and some who only fed once) and this is compared to non-breast fed.
Now it is better as the category is broken down more into how much breast feeding they received.
Mechanism published suggesting why this might happen. Specific fatty acid found only in human and donkey milk, work through an immune mechansim to convert thermogenic beige adipocytes into white adipocytes which store fat. Breast feeding can prolong the conversion so keep more thermogenic cells.
Brain development
-The 2 groups had comparible head circumferences which is measure of development.
Brain development
Maternal health
Breast cancer is divided into 5 groups
It is the triple negative that have the worse prognosis and effect younger women.
Maternal health
Women with BRCA1 are told not to breast feed as need can at 6 months which can lead to false positives on scan.
This is bad as could be the one way of reducing their risk of cancers.
Evolutionarily if lactation didnt happen after birth it would be because the baby had died. Breast feeding grief-if feeding cant happen
Any breastfeeding?
There is a huge drop in continual breast feeding in the UK.
What is normal lactation?
Prolactin produced by HPA axis helps lactate cells to secrete milk and oxytocin causes secretion by binding to myometrium on breast.
Greater baby feeds the more milk-feedback mechanism
BF difficulties:
Collapse in breast feeding in the last years, so women are coming up with these ideas that could have been helped if they got the right support.
How often do babies breastfeed?
Huntergathers-feed often but for short times as this is essentially them staying hydrated and long feeds is proper meal
Babies feed constantly, especially when cluster feeding-essentially feeding solidly for 6 hours. This is to ramp up full capacity to feed.
This is often when mistakenly formula is given, when baby ist trying to feed but is ramping up mothers supply so if baby is fed it prevents mothers supply being increased.
Newborn patterns
Factors that can decrease supply
Anything that interupts the mother being with the baby.
Feeding cues are often missed if babies are given a dummy (mainy in early stages)
Responsive feeding is associated with:
eye contact-mum understanding babies needs as babies are very good at signalling what they need
Responsive feeding
keep babies in slings, not prams so they are facing the care giver
Feeding at night
But what does responsive feeding really look like?
Sling rather than pram
Where can women find help?
Specialist lactation consultant-take 3 years to specialise, very knowedgable.
Prescribing advice
Very few drugs that are contraindicated.
Drug companies don’t have to test these drugs before licensing so this is not well investigated.
Try and keep baby on breast milk and don’t just tell her to stop. Look up
Where can doctors find help and info?
What about when you can’t breastfeed?
How effective is exclusive donor milk?
Global picture
4 mo+ sleep
Normal sleep
ISIS:
Comparison with formula feeding
Normal weight gain
Normal weight loss
On the impact of love
Crying
Normal needs
