FoundMyFitness - #056 The Biology of Breast Milk

Episode Date: August 25, 2020

This episode aims to be the most comprehensive video compendium on the biology of breast milk ever recorded. In this episode, you'll discover: (00:00) Introduction (07:11) Breast milk production and composition (09:59) Human milk oligosaccharides help establish the infant gut microbiome (16:32) Omega-3s in breast milk boost brain development (18:15) Vitamins and minerals in breast milk (22:05) Breast milk stem cells and multi-organ microchimerism (22:54) Harmful substances transferred to infants via breast milk (28:05) Breastfeeding boosts the infant's immune system (31:17) Effects on intelligence (34:36) Breastfeeding as a benefit to maternal health If you're interested in learning more, you can read the full show notes here. Join over 300,000 people and get the latest distilled information on the biology of breast milk straight to your inbox weekly: https://www.foundmyfitness.com/newsletter Become a FoundMyFitness premium member to get access to exclusive episodes, emails, live Q+A's with Rhonda and more: https://www.foundmyfitness.com/crowdsponsor

Hello friends. I'm very excited to share today's episode with you. As a mother, it covers a topic that is very near and dear to my heart, a topic that has to do with infant and child development. That topic is the biology of breast milk and the enormous health benefits breastfeeding has for both the infant and mother. We're going to dive deep into the science of breast milk on this one, including breast milk composition and production, how human milk oligosaccharides, in breast milk establish the infant gut microbiome and protect from bacterial infection. How omega-3 fatty acids that find their way into breast milk as a result of the mother's diet and supplementation may boost brain development. Which vitamins and minerals are robustly

passed to the infant through breast milk and others that are poorly transferred. How breast milk contains stem cells that can help with infant development and may even integrate into intact organ systems in the infant's body. How harmful substances can be transferred to the infant via breast milk. How breastfeeding improves the infant's passive and active immune system and even forms a compensatory immune system where infant infection generates a rapid response that beneficially alters the mother's breast milk, arming the infant to fight infection. How breast milk improves infant brain development with special relevance to infants born prematurely. How breastfeeding benefits mothers by reducing the risk of ovarian and breast cancer, and so much more. But before we get

started, I want to quickly mention a couple of things. First, co-released with this episode today is a sample of a brand new episode format we are calling an aliquot. What is an aliquot, you may ask? Aliquots are special curated segments prepared and distributed to premium members via the premium members podcast feed. Aliquots in a sense are all about curation. We're excited about aliquots as just one more great benefit that we can bring to members while ultimately creating a useful format that is to the benefit of the public and supports the free content we produce, like today's episode. With that said, our co-released preview of the very first aliquot is in many ways an extension

of today's episode. It is focused on the many, and I mean many, questions I've taken on the topic of pregnancy and child development from members during the members-only question and answer sessions. Just for a few examples, it covers my pre-pregnancy regimen, including diet, exercise, vitamins, and sleep, nutrition for babies and toddlers to maximize brain development and growth, extra precautions that I took during my pregnancy, and much, much more. So if you enjoy this episode today and you're interested in my continued thoughts on pregnancy and child development topics, take a listen to a preview of our

very first Alawquot episode now. You can also find more Alawquot episode previews and information about this new type of curated members content at foundmyfitness.com forward slash aliquot, A-L-I-Q-U-O-T, A-A-Q-O-T. The other thing that I wanted to mention is this episode you're about to listen to on breast milk is also an article and a video. My team and I literally spent several months combing over the scientific literature on breast milk. We read dozens of studies and published a fully referenced article that goes into great detail on breast milk and breastfeeding and then went on to take the best parts and also put them on the screen during the actual video. These summaries and graphics can at times be a really big help. Find the article by going to Found My Fitness,

com and looking for breast milk under the topics section and find the video by heading over to foundmyfitness.com forward slash episodes now onto the podcast dr ronda patrick here today we are going to discuss a topic that's been near and dear to my heart something you could say i've needed to get off my chest that subject is the science of breast milk nutrition in the first year of life is crucial to an infant's development and lifelong health, with the power to impart a lasting legacy on mental growth, physical growth, and even setting the barometer for our potential to fall prey to diseases like obesity, diabetes, and hypertension. The science of breast milk, both in relation to its composition and its function, put on full display the myriad of ways that evolutionary forces have converged to create a special

form of nutrition, interaction, immunological preparation, and more. All subtle optimizations that broaden the scope of the place and role simple nourishment activities have in early life. In today's episode, we're going to talk about breast milk and a ton of interesting science on how breast milk contains complex indigestible sugars called human milk oligosaccharides, how it contains immune cells that respond to the infant mother immune status. How breast milk contains stem cells. Yes, stem cells. And what this all means for the health

and even brain development of the infant. The American Academy of Pediatrics recommends exclusive breastfeeding, which means no formula or other foods for the first six months of an infant's life. And then continued breastfeeding while introducing age-appropriate foods until an infant is 12 months old.

Among babies born between 2010 and 10, 2013, approximately 80% were breastfed initially, but only 20% of those children were breastfed exclusively at six months of age. For all those reasons and more, today's conversation is important. We're going to talk about a lot of the unique ways breast milk nourishes infants, while also acting as an enormous boom to immunity in a two-way type of biological communication between mother and infant and indeed much more. Before we start with all I've done so far and we'll continue to do in this episode to emphasize the bounty of nourishment of breast milk, as well as its unique properties,

I'd like to say that none of this is to diminish the hard work of mothers with formula-fed or partially formula-fed infants. I think it's important to remark on the amazing power of the human organism to not only adapt, but thrive and excel in sometimes broad ranges of optimal. and vastly different conditions. I'll sidestep the popular refrain of Fed is best, which may be Lyle some of the nuance we will hopefully enjoy during this conversation that does not highlight some of the important and utterly unique beneficial factors of breast milk and breastfeeding.

Instead, we shall say, Fed is fundamental, and sometimes getting in the fundamentals is what counts. Let's start with some of the basics. Breast milk production and composition. The first fluid that a mother produces is colostrum, a thick, sticky fluid that typically is yellow, orange, or white in color. Since colostrum contains a slew of immune factors, its primary role is immunological, rather than nutritional. Some women can express colostrum in the last few months or weeks of pregnancy. Next comes transitional milk, which arrives during the first few days to two weeks after childbirth and is high in lactose. By four to six weeks after childbirth, the mother's

milk is considered mature. Mature milk that is expressed during the early part of a single feeding session is called four milk. It's high in lactose and has a watery consistency. The milk expressed during the latter part of this feeding is called the hind milk. It's high in fat and has a creamy consistency. Breast milk is an incredibly dynamic substance. It changes in composition during a single feeding from day to night and throughout the lactation period in response to the growing infant's needs. It's also influenced by circadian rhythms. Breast milk contains several components that transmit circadian signals to help the infant regulate its own sleep wake cycle with the nighttime breast milk containing higher levels of melatonin and somnogenic amino acids like

tryptophan. Breast milk nucleotides, which are important structural components of DNA and RNA, also show circadian rhythmicity. Some of the nucleotides peak during the day while others peak at night, suggesting a potential role for these nucleotides as sleep inducers. These data suggests that if an infant is fed expressed breast milk, the milk should be provided at the same time of day that it was expressed to maintain the infant circadian rhythm. It's important to note that things you eat, drink, supplement, but even more importantly, smoke can end up in your breast milk. Breast milk is species specific. Human breast milk contains proteins, carbohydrates, fats, vitamins, and minerals to nourish a human infant. One of the biggest differences you'll see between human

milk and other types of milk is the protein content. The total protein content in human breast milk is quite a bit lower than milk from other species. One of the reasons human infants grow so slowly compared to, say, a calf. There are roughly 415 different proteins in human breast milk. These proteins provide nutrition, but they also aid in the infant's digestion and supply both antimicrobial and immunological factors that compensate for deficiencies in the infant's immune system, which I'll talk about a little bit later. Breast milk contains a variety of complex carbohydrates, the most abundant of which is lactose, which provides necessary energy for the infant's brain.

The second largest concentration of carbohydrates in human breast milk are non-nutrative components called human milk oligosaccharides, or HMOs for short. So let's talk about HMOs, a fascinating part of, the story of breast milk. HMOs are complex in digestible sugars. More than 200 different HMOs have been identified in breast milk, making them the third most abundant factor in human breast milk after lactose and fat. These things are super abundant, but here's the surprising part. They aren't there to feed the baby. Instead, HMOs have a very special purpose, which is setting up and feeding and ultimately creating the conditions to select for a strong population of commensal,

in other words, healthful bacteria in the infant gut. The origin story of HMOs is similar to those of other examples of neutralism we find throughout the world of biology. Bacteria that benefit us, such as bifidobacteria, get a boost from our own biology as a function of breast milk, whereas bacteria that harm us, pathogenic bacteria, are discouraged from establishing a foothold through a variety of mechanisms. These good bacteria then go on to help set up the immune system through the production of various signaling molecules, such as short-chain fatty acids, which are metabolites produced from the gut

bacteria after they metabolize the HMOs. These substances prevent colonization of pathogenic bacteria in the gut. I previously spoke with experts on the gut microbiome, doctors Justin and Erica Sonenberg, who spoke a little bit on the topic of HMO. So babies that are fed formula, their microbiota looks very different than breast milk. And actually what we see is breast milk has a component of it. One of the major components of breast milk is this type of carbohydrate called human milk oligosaccharides or HMOs. And for a long time, it was really a mystery why those molecules were there, because we knew that humans can't digest human milk oligosaccharide. So why would a mother put so much effort into creating these compounds and putting them in her milk?

if her baby can't even digest it, we'll come to find out it's actually the gut microbes that are digesting these HMOs. So in breast milk, there's not just food for the baby in the form of lactose and fats, but these HMOs that are food for the babies growing microbiota. So the mother's feeding the baby and also her baby's growing microbiota. And these HMOs are very specific for human milk and so far have not been able to be replicated in formula. And so that we think is a large reason why the communities are so different.

And then, of course, antibiotics, the average American child is on a round of antibiotics every year. And we know that that's a huge, makes a huge impact on that growing community. So all these things that happen early in life could really set a child on a trajectory potentially for having potentially a very good, healthy, robust microbiota or potentially one that isn't as good. And so I think as parents, especially of new children, we need to be very mindful of the choices that we make early in a child. life because many of these microbes that we have by the time we're, say, the age of five, many of these microbes will be with us throughout our entire life. So we really want to get that community started in the best possible way. And nature has come up with a way to get that microbial community started in the best

possible way, breast milk. But that's not the end of the story of HMOs. They also serve as decoys to protect the infant from gut infections. In order for bad bacteria to cause infection, they must first target and start, bind to specific carbohydrates found on the cells that line the gut. However, the overall structure and shape of HMOs mimics that of bacterial targets. The bad bacteria bind to the HMOs instead, preventing them from establishing themselves in the gut. Another interesting quality of HMOs is their capacity to break down biofilms, sticky, slimy communities that bacteria create

to protect themselves from antimicrobials and antibiotics. Not only that, they appear to enhance the activity of some antibiotics by increasing the membrane permeability of pathogenic bacteria. So, to sum up HMOs, they're the third most abundant factor in human breast milk after lactose and fat, and they play roles in establishing an infant's gut microbial community, a key component of the immune system. They also protect the gut from harmful bacteria by serving as decoys and breaking down the communities in which these harmful bacteria live.

Fats are the major source of energy provided in breast milk, supplying roughly half of its total calories. Fats provide energy for growth, aid in the maturation of the infant's gut and central nervous system, and provide protection from pathogens, including Group B streptococcus bacteria. Nearly 200 fatty acids have been identified in human breast milk. The structural configuration of these fats, which is not always replicated by many infant formulas, enhances their absorption in the infant's gut. All of these fats are encapsulated in fat globules surrounded by a triple-layered structure

called milk fat globule membrane, or MFGM. Components of the MFGM exert bioactive properties that confirm many of the antibacteriore in anti-inflammatory properties of breast milk. Unfortunately, most infant formulas do not contain MFGM. However, a recent clinical trial found that bovine form of MFGM exerts similar beneficial effects on human infants when included in infant formula. The double-blind, randomized controlled trial involved 451 healthy, full-term infants who received either regular formula or formula containing MFGM and lactoferrin.

an iron binding protein found in human and cows milk. At the end of the 18-month-long study, the infants who received formula with the MFGM and Lactoferrin scored higher on cognitive, language, and motor skills than infants who received ordinary formula. In fact, their scores were similar to those observed in children who were breastfed, suggesting that the addition of MFGM and lactoferrin could narrow the gap in cognitive development commonly observed between formula-fed infants and breast-fed infants. The type of fatty acids present in breast milk are strongly influenced by the mother's diet, especially when it comes to the all-important omega-3 fatty acids. For example, when lactating women took a dietary supplement containing 400 milligrams of the marine omega-3

fatty acid DHA, their breast milk contained 123 percent more DHA than the breast milk of women who took a placebo. DHA is crucial for proper brain development. The infants whose mothers took the DHA supplement also had lower plasma omega-6 to omega-3 ratios. A lower omega-6 to omega-3 fatty acid ratio is more desirable in reducing the risk of many chronic diseases. Smoking cigarettes reduces omega-3 fatty acid uptake, especially DHA, into breast milk.

Omega-3 fatty acids play key roles in infant brain development. intake of DHA in particular is associated with improved mental and psychomotor development. DHA is the most abundant omega-3 fatty acid in a newborn's brain. Maternal intake of omega-3 fatty acids is associated with larger brain volumes in breast-fed or mostly breast-fed infants. One study involved 92 one-month-old full-term infants who were breast-fed exclusively or most of the time. MRI studies reveal that the infants of women who consumed higher quantities of omega-3 fatty acids had greater brain volumes and specific regions of the frontal cortex and corpus callosum, areas of the brain involved in consciousness,

communication, memory, attention, and integration of motor, sensory, and cognitive performance between the brain hemispheres. Breast milk also contains vitamins and minerals, but these vary based on a mother's diet and tissue stores. If the mother is undernourished or eats an unhealthy diet, her breast milk may be inadequate to supply sufficient quantities of essential micronutrients to her infant, and supplementation for the mom, infant, or both, may be necessary. However, some nutrients are low in breast milk regardless of the mom's diet. For example, vitamin K1, which is essential for normal blood clotting, is very low in breast milk. Consequently, the American Academy of Pediatrics recommends that all newborn infants receive an injection of

K1 to prevent hemorrhaging shortly after birth. Iron is an essential nutrient that plays key roles in infant growth, but breast milk is incredibly low in iron, which might seem counterintuitive. However, microbes require iron for their growth too. To prevent infection, the body restricts microbes access to iron. Within hours of birth, the infant's serum iron levels drop dramatically. This reduces the infant's risk of developing neonatal sepsis, a generalized life-threatening bacterial infection that commonly occurs within the first days and weeks of life. Infants rely on their iron stores, but by the age of six months, infants can begin to develop iron deficiency anemia. So pediatricians recommend introducing iron-rich complementary foods at that time. Breast milk also contains

very little vitamin D, certainly not enough to prevent vitamin D. Certainly not enough to prevent vitamin D. deficiency in exclusively breast-fed infants. But recent studies have shown that moms who take a daily high-dose vitamin D supplement of 6,400 IUs a day can increase the vitamin D concentration of their breast milk to a level that provides sufficient vitamin D intake for their infant. And in more bad news about smoking, maternal cigarette smoking impairs the uptake of some nutrients into breast milk. For example, iodine concentrations in the breast milk. For example, iodine concentrations in the breast milk of women who smoke are roughly half of those of non-smoking women's breast milk. Iodine is critical for brain development and is also important for thyroid function.

Rodin studies have found that maternal nicotine exposure impairs thyroid function in offspring and promotes resistance to the hormone leptin, which is associated with obesity. Smoker's breast milk has lower levels of antioxidant vitamins, vitamin C and E, which could drive a pro-oxative state in the infant. This was demonstrated in a really interesting study where researchers measured levels of ethane, a marker of oxidative stress, in the exhaled air of infants. The breastfed infants of women who smoked exhaled seven times more ethane than the infants of women who did not smoke. Research indicates that exposure to cigarette smoke influences breastfeeding duration. A study of more than 1,200 mother infant pairs found that women who were

exposed to household secondhand smoke were 30% more likely to stop breastfeeding early compared to women who were in non-smoking households. Contrary to the belief that human milk is a sterile solution, breast milk is teeming with hundreds of types of bacteria. They arrive in the mother's milk from a variety of sources, including the mother's skin, retrograde flow from the infant's saliva, aka backwash, and potentially other means. Exposure to this rich bacterial community via breast milk may contribute to the differences observed in gut microbial populations between breastfed and formula-fed infants and provides a rationale for the inclusion of probiotics in infant formulas. Another amazing component of breast milk is stem cells.

Human breast milk contains stem cells from the mother called mammary stem cells that preclinical research indicates may help establish organs like the liver, kidneys, pancreas, and brain. In a really cool study in mice in which mammary stem cells were followed, it was found that in the liver they form cells that make albumin, in the pancreas they form insulin producing cells, and in the brain they formed neurons and glial cells. This phenomenon where cells from the mother are found in the offspring and remain there long term is called microchimerism. What this data suggest is that breast milk transmits stem cells from the mother to the infant, where these cells may potentially function to boost in infant's development early in life. Other things can be transferred from the mother's breast milk

as well. A whole slew of harmful substances can transfer from the mother's blood into her breast milk. For example, heavy metal concentrations like cadmium are increased in breast milk. Cadmium impairs the metabolism of nutrients essential to infant development, including selenium, zinc, copper, and magnesium. If that's not bad enough, cadmium is also a carcinogen. Cadmium levels in the transitional milk of women whose smoke are approximately four times higher than the milk of women who don't smoke. Most drugs can be taken up into breast milk via passive diffusion, but how much ends up in the breast milk depends on the drug size and chemical characteristics, but also factors that alter the mom's drug metabolism. An infant's capacity to metabolize drugs is much lower than the adult,

especially in the early weeks of life. So most of the adverse events related to maternal drug use occur in infants less than two months of age. Drugs that should absolutely not be taken during breastfeeding include anti-cancer drugs, lithium, oral retinids, high-dose iodine, amiodarone, and gold salts. But even drugs considered social drugs, including alcohol, nicotine, caffeine, and cannabis can carry some risks to the infant. Alcohol also passes into breast milk, but the amount that an infant is exposed to is low due to the infant's high body water content. Unfortunately, infants detoxify alcohol less efficiently than adults do, so high maternal alcohol intake could have negative effects on breastfed infants, including altered sleep patterns,

decreased milk intake, weight gain, alcohol-induced hypoglycemia, and impaired motor development. Alcohol metabolism occurs according to zero-order kinetics. That means that it is broken down at a constant rate, so drinking water, exercising, or pumping and dumping won't speed up the process. Nicotine transfers into breast milk too and can have harmful effects on infant health. Nicotine concentrations in breast milk of women who smoke are three times higher than the mom's plasma levels. But an infant's capacity to eliminate nicotine is three to four times less than that of the adult.

A study involving 15 mother infant pairs found that infants slept approximately 30 minutes less when they were fed immediately after the mother smoked. compared to when they were fed after the mother abstain from smoking. And the babies of women who smoke cigarettes are more susceptible to respiratory infections and colic and typically exhibit poor respiratory function after breastfeeding. Not only does nicotine affect the infant, but it also impairs milk production by altering levels of maternal prolactin, the principal hormone involved in the production of milk. Quitting smoking can be very difficult, though.

Nicotine patches might be a good option for women who are having problems quitting. Breast milk concentrations of nicotine obtained from nicotine patches are approximately 70% lower than those obtained from smoking. On the other hand, findings from a rodent studies show that even low levels of nicotine exposure during pregnancy or early in life can increase the risk of sudden infant death syndrome or sits by inhibiting the neonate's ability to auto-rescitate. Of course, many women's favorite drug is caffeine. It's found in a wide variety of foods and beverages. My favorite is coffee. And it's founded other products as well, such as gum.

The amount of caffeine present in breast milk varies according to differences in the mother's caffeine metabolism, and is typically low, approximately 1% of the maternal blood concentration, which usually peak one to two hours after ingestion. But caffeine metabolism is very poor in infants. So infants of women who consume extremely high quantities of caffeine, 750 milligrams per day or more, which is about six to eight cups of coffee, could potentially achieve toxic concentrations of caffeine from breast milk. Cannabis is a broad term for the psychoactive components of the marijuana plant. Breast milk samples from 50 lactating women who reported using marijuana showed that 63% of the samples

contain detectable levels of THC, the primary psychoactive ingredient in marijuana. These levels were present up to six days after the last reported use. Marijuana exposure via breast milk during the first month of an infant's life is associated with decreased infant motor development at the age of 12 months. So just to summarize, a slew of harmful substances can transfer to a mother's milk, such as heavy metals and prescription drugs, especially those used to treat cancer and several others. Babies don't metabolize drugs as well as adults, so women who require these drugs should

discuss whether breastfeeding is a safe option. But alcohol, nicotine, caffeine, and cannabis all carry some risk to a breastfed infant. So caution is advised even when using these common social drugs. Let's discuss some more benefits of breastfeeding, starting with the immune system. An infant's immune system is the last of the biological systems to develop, taking months or even years to match that of an adult's capacity for defense. Breast milk contains a multitude of components that work together synergistically to provide a compensatory immune system, including antimicrobial agents like lactoferrin, secretory

IGA, lactoalbumin, lysosyme, and monolorin, anti-inflammatory agents like interleukin, IL-10, lactoferrin and lysosine, immunomodulatory factors like memory T cells, IL4, IL-10, IL-12, colony stimulating factor 3, tumor necrosis factor alpha, interferon gamma, and leukocytes, among others. These varied components confer both passive and active immunity. A critical element of the infant's active immunity is provided by maternal leukocytes, living white blood cells that provide protection from infection in the infant's gut and other tissues. Concentrations of leukocytes are highest in colostrum and taper off in transitional milk,

eventually reaching a baseline level in mature milk. But if the infant, mother, or both develop an infection, that, level can increase up to 94% above baseline. Although experts recommend exclusive breastfeeding for at least six months, children who are breastfed for any length of time are 64% less likely to develop non-specific gut infections, an effect that last as long as two months after the cessation of breastfeeding. Similarly, infants who are breastfed for at least three months have lower risk of developing atopic dermatitis, also known as eczema. Meta analyses of randomized controlled trials, prospective studies, and case-controlled studies demonstrate that infants exclusively

breastfed for more than four months are 72% less likely to be hospitalized due to lower respiratory tract infections in the first year of life compared to infants who were fed formula. And infants who were breastfed for six months or longer had a 20% lower risk of developing acute lymphocytic leukemia and a 15% lower risk of developing acute myeloid leukemia. That's not all. That's not all. All, emerging evidence suggests that some of the immune and health benefits that infants acquired during breastfeeding may be lifelong. For example, breastfeeding appears to confer long-term protection to the gut. Infants who are breastfed are 31% less likely to develop childhood inflammatory bowel disease

and 52% less likely to develop celiac disease if breastfed at the time of gluten exposure. Recent animal studies demonstrate that female mice that are exposed to infection before pregnancy may pass on lifelong immunity to their offspring via the transfer of immune cells in their milk even after nursing stops. So just to recap, breast milk contains a multitude of components that work together synergistically to provide a compensatory immune system that confers both passive and active immunity. This provides protection against respiratory infections and certain types of cancer in childhood and might even contribute to lifelong immunity. Breastfeeding also has profound effects on an infant's brain, greatly influencing their intellectual development.

A meta-analysis of 17 studies linking breastfeeding and intelligence found that children and adolescents who were breastfed as infants scored nearly three points higher on intelligence tests than those who were not breastfed, even after taking maternal intelligence into consideration. A large clinical trial that followed up on more than 13,000 infants from around 13 different hospitals found that total and exclusive breastfeeding led to improve performance and intelligence test at the age of six, with breastfed children averaging roughly 7.5 points higher on tests than children who were not breastfed. Other research has found that by the age of two, babies who were exclusively breastfed for at least three months had 20 to 30 percent

more white matter in their brains, especially in regions associated with language, emotional regulation, and cognition. The better. Beneficial effects of breast milk on infant brain development may be particularly relevant for preterm infants born prior to 37 weeks gestation, who have a significantly higher risk for white matter injury during birth. Approximately 1 in 10 infants born in the United States is born prematurely, according to CDC data. Emerging evidence suggests that preterm infants who are fed breast milk have significantly

improved microstructural organization of the white matter in their brains compared to preterm infants fed formula. preterm babies that receive breast milk in the neonatal ICU or NICU have higher verbal intelligence, white matter, and total brain volumes, especially in boys. So in summary, breastfeeding influences brain development and intelligence, even after taking maternal intelligence into consideration. Breast-fed babies tend to have higher amounts of white matter in their brains and later in life perform better on intelligence tests than non-brest-fed babies. breast milk may also protect against cardiovascular complications. Preterm babies are more likely to have

cardiovascular complications, including small ventricle size, heart muscle hypertrophy, and poor blood pressure control. Most of these complications are often manifested in adulthood, as increased risk of ischemic heart disease, hypertension, and poor metabolic function. Some evidence suggests that breast milk mitigates some of the cardiovascular related complications associated with preterm birth. Most of the data about the cardioprotective effects of breast milk in preterm infants comes from follow-up studies of a cohort of more than 900 preterm infants born in the UK. The babies in the studies received either donor breast milk or a nutrient-enriched preterm formula exclusively until their body weight reached 2,000 grams. When a subset of those babies reached adulthood, 23 to 28 years

of age, their cardiovascular health was assessed. Those who had been fed breast milk exclusively as preterm infants had larger ventricle size and stroke volume compared to those that just had been formula-fed. A separate follow-up study found that the infants that received breast milk exclusively had lower diastolic and systolic blood pressure at the age of 13 to 16 years. So it seems as though breastfeeding may mitigate some of the cardiovascular-related complications associated with preterm birth, many of which can manifest later in life as eschemic heart disease, hypertension, and poor metabolic function. Breastfeeding also has benefits for mothers as well. A review of 47 epidemiological studies found that for every 12 months of breastfeeding, the risk of developing breast cancer was reduced

by 4.3%. Findings from a case control study of more than 400 women with ovarian cancer suggests that even short-term breastfeeding reduces the risk of developing ovarian cancer. Weight gain is a normal healthy part of pregnancy. Losing weight after pregnancy is difficult for many women, but those who breastfeed are more likely to return to their pre-pregnancy weight, and they typically do so sooner, within the first three to six months after delivery than women who do not breastfeed. When it comes to breastfeeding, there are practical aspects and challenges. An important question that many mothers have is, how long should I breastfeed? As mentioned before, the American Academy of Pediatrics recommends exclusive breastfeeding

for about six months, followed by continued breastfeeding as complementary foods are eating. introduced with the continuation of breastfeeding for one year or longer, as mutually desired by mother and infant. The World Health Organization also recommends exclusive breastfeeding for up to six months of age, with continued breastfeeding along with appropriate complementary foods, up to two years of age or beyond. The first few days and weeks of breastfeeding present many challenges to new mothers, ranging from sore nipples and plugged ducks to lack of family support and other concerns. Working with a lactation consultant during the first few weeks of breastfeeding may be helpful. If a woman's milk is insufficient to meet the need of her infant or if she has a health

concern that prevents her from breastfeeding, donor milk may be an option for healthy, full-term babies. One more thing, it's important to realize that talking about the benefits of breast milk and breastfeeding infants is not the same thing as criticizing mothers who, for whatever reason cannot or choose not to breastfeed. In summary, breastfeeding provides many benefits to both infants and mothers, including intellectual and emotional development in the infant, and protection against cancer and obesity in the mother. Breast milk provides a compensatory immune system for the infant. Breast milk is a complex, dynamic fluid that contains a multitude of nutritional and non-nutritional components, including immune cells, stem cells, and human milk oligosaccharides.

Breast milk also provides a mechanism for the transfer of substances or drugs that the mother may inhale, ingest, or absorb to the benefit or possible detriment of the infant. Although breastfeeding presents challenges to some women, support is available. I'm Dr. Ronda Patrick, and I'll catch you next time. Thank you so much for listening. We hope you enjoyed today's episode. Just as a reminder, if you're interested in learning more about this topic, we just released a free preview of our very first. Aalquot episode available now on our podcast. It features a compilation of pregnancy and child development related topics taken from my Q&A episodes over the last couple of years. This episode covers things like

my pre-pregnancy regimen, including diet, exercise, vitamins, and sleep, nutrition for babies and toddlers to maximize brain development and growth and extra precautions that I took during my pregnancy, and so much more. It's the first of three Alawquod episode previews we'll be releasing publicly over the next few weeks, so be sure to look out for those soon. If you're wanting full access to the Alawquot today, head over to foundmyfitness.com forward slash Aalquot. You'll get instant access to full episodes and timelines with time codes for each topic and much more. Thanks so much and talk to you guys soon.