What happens in infancy sets the stage for metabolic function, immune balance, and disease risk later in life. One of the most important choices during this stage in your child’s life is whether to breastfeed them or not — and recent research provides more solid evidence that breastfeeding has lasting health consequences. A study found that children who were breastfed longer had a more diverse gut microbiome, which directly correlated with lower blood pressure in early childhood.
This is a significant finding, especially since high blood pressure is a growing problem in today’s youth. According to some estimates, up to 7% of children are now dealing with high blood pressure,1 which raises their risk for heart disease and stroke later in life.
Breastfeeding Shapes Your Baby’s Gut Health and Lowers Blood Pressure
A recent observational study published in the Journal of the American Heart Association investigated the link between infant gut microbiome diversity and blood pressure in early childhood. Researchers examined how breastfeeding influences gut bacteria composition and whether this, in turn, affects blood pressure development by the age of 6.2
• Investigating the connection between infant gut bacteria and blood pressure — The study involved 526 children from Denmark who were tracked from infancy through early childhood. The researchers analyzed stool samples to assess gut microbiota diversity at different stages of infancy, comparing these results with blood pressure measurements taken at ages 3 and 6.
• Breastfeeding helped diversify children’s gut microbiome — They found that children who were breastfed for at least six months had a more diverse gut microbiome, with a greater presence of beneficial bacteria such as Bifidobacterium. This bacterial strain is known to help maintain gut health, reduce inflammation, and support immune function.
• Higher gut microbiota diversity in infancy is directly correlated with lower blood pressure later in childhood — Specifically, the study found that a one-unit increase in gut microbiome diversity at one month of age was associated with a 1.86 mmHg decrease in systolic blood pressure at age 6. This is significant because even small reductions in childhood blood pressure lower the risk of hypertension and cardiovascular disease later in life.
• The duration of breastfeeding played a crucial role — Babies who were exclusively breastfed for six months or longer showed the greatest benefit. Their gut microbiomes were significantly more diverse than infants who breastfed for only a short period or given formula early on. The blood pressure-lowering effect was strongest in this group, highlighting the importance of sustained breastfeeding for long-term cardiovascular health.
• Infants who were formula-fed had a less diverse microbiome composition — They also had a higher presence of harmful bacteria. The difference in microbial composition between breastfed and formula-fed infants appears to be a key factor in why breastfeeding supports healthier blood pressure outcomes.
• Even partial breastfeeding (breastfeeding alongside formula feeding) had some benefits — However, the effect was weaker. The more formula introduced early in life, the less protective the gut microbiome appeared to be. This suggests that exclusive breastfeeding, particularly for six months or more, provides the greatest advantage in shaping a healthier microbiome that supports optimal blood pressure regulation.
How Does Your Gut Bacteria Influence Blood Pressure?
The researchers believe there are several reasons why gut health affects blood pressure. One reason is that some types of beneficial bacteria have evolved specialized biologic functions that allow them to transform indigestible carbohydrates in breastmilk into calories and substances that are used by your infant’s body.3
• Specific bacteria strains break down carbs — Bifidobacterium species, including B. infantis, are highly efficient in breaking down carbohydrates and turning them into short-chain fatty acids (SCFAs), which influence blood pressure levels.
• Gut microbes play a role in regulating inflammation — They do this by producing beneficial compounds and maintaining the integrity of the gut lining. A diverse gut microbiome, rich in beneficial bacteria, produces more SCFAs, which have been shown to lower blood pressure.
• SCFAs help relax blood vessels — SCFAs like butyrate and acetate improve blood vessel function and promote smoother blood flow, which helps prevent hypertension.4 They also communicate with the immune system, reducing the chronic, low-grade inflammation that contributes to high blood pressure.5
• Infants who are not breastfed are at risk of leaky gut — Since formula-fed infants do not get the healthy carbs from breastmilk, their gut bacteria break down carbohydrates that line the intestines instead. This leads to leaky gut, a condition where the intestinal lining weakens and allows bacteria and fat to enter the bloodstream, triggering inflammation and increasing blood pressure.6
• Interestingly, gut microbiome’s impact on blood pressure was independent of body weight — Some might assume that children with lower blood pressure were simply those who had lower body weight or healthier metabolic markers, but this study controlled for those factors. Even among children with similar weight and BMI, those with greater microbiome diversity in infancy had significantly lower blood pressure at age 6.
These findings prove that breastfeeding does far more than provide nutrition — it actively programs the gut microbiome in a way that supports your child’s long-term health and helps protect against heart disease.
Breastfeeding Strengthens Your Baby’s Gut Health
Another study published in the Journal of Allergy and Clinical Immunology examined how breastfeeding influences the development of a child’s gut microbiome and immune system. Researchers explored how breastmilk components shape bacterial colonization in a child’s gut, which in turn affects immune function and disease risk later in life.7
• Analyzing the gut of breastfed and formula-fed infants — The researchers studied the gut microbiomes of the infants to determine how breastmilk influences bacterial composition. One of the most important findings was that breastfed infants had a significantly higher presence of Bifidobacterium.
• Breastmilk contains unique compounds — They also found that human milk contains oligosaccharides (HMOs) and secretory immunoglobulin A (SIgA) that selectively feed beneficial bacteria while preventing harmful bacteria from taking over.
• Breastmilk also acts as a natural prebiotic — HMOs serve as food for specific bacteria like Bifidobacterium. Unlike standard sugars that provide energy to the baby, HMOs pass through the digestive system untouched by human enzymes, feeding only beneficial gut microbes. This process gives breastfed infants a major advantage, as their gut bacteria become optimized for better digestion, immune support, and disease protection.8
• Formula-fed infants had more inflammatory gut bacteria — Aside from having fewer Bifidobacterium, the researchers also found a higher presence of Clostridium and Proteobacteria in formula-fed infants. These bacteria have been linked to gut inflammation, increased intestinal permeability, and a higher risk of immune-related disorders.
Breastmilk Builds Your Infant’s Natural Immunity
According to the study, another major benefit of breastfeeding is the direct transfer of immune-supporting antibodies. Secretory immunoglobulin A (SIgA), a specialized antibody found in human milk, helps coat your infant’s gut lining, acting as a natural defense barrier against harmful bacteria and viruses.9
• Higher SIgA levels contribute to better immune regulation — SIgA works by binding to harmful pathogens, preventing them from attaching to your infant’s gut lining and causing infections.
• SIgA also develops immune tolerance — It helps your infant’s immune system learn to differentiate between harmless substances and real threats. This is particularly important in early life, as an overactive immune response increases the risk of autoimmune conditions and allergies later on.
• Breastfeeding lowers inflammatory markers — Chronic inflammation in early life leads to a wide range of health problems, including asthma, allergies, and metabolic disorders. By promoting beneficial gut bacteria and reducing harmful microbial activity, breastfeeding plays a crucial role in keeping inflammation in check.10
The study also noted that introducing formula too early disrupted the natural colonization of beneficial bacteria, weakening many of the advantages seen in exclusively breastfed babies. This reinforces the importance of exclusive breastfeeding during the first six months for optimal immune and gut health.11
Choose Breastfeeding Over Formula Milk
If you want to give your baby the best foundation for lifelong health, breastfeeding is one of the most powerful choices you can make. There's no doubt that breastmilk is the best first food for your child — Colostrum, the first milk you produce after birth, has been even dubbed “liquid gold” not just for its yellow color,12 but also for its impressive nutritional content.
Unlike formula, breastmilk offers a unique blend of antibodies, immune factors, hormones and stem cells that tailor themselves to the needs of your child. Breastmilk is dynamic, adjusting its composition in response to cues from the infant’s saliva and feeding frequency. The two studies featured above prove that there’s a consistently growing body of research highlighting its benefits.
For more information on why breastfeeding is superior, read “The Power of Breastfeeding.” If you’re a new parent, or expecting, here’s how to ensure your baby gets the healthiest start possible.
• Breastfeed exclusively for at least six months — As these two featured studies demonstrate, your baby’s gut bacteria and immune system are developing rapidly in the first six months of life. Breastfeeding exclusively during this time gives them the highest levels of Bifidobacterium, the beneficial bacteria that protect against inflammation and support gut health.
Introducing formula milk too early disrupts this balance and weakens many of the benefits of breastfeeding. Stick with breastmilk alone for six months to maximize your baby’s long-term health.
• Prioritize your own nutrition while breastfeeding — What you eat directly affects the quality of your breastmilk. To support your baby’s gut microbiome, focus on whole, nutrient-dense foods that are free from seed oils and excess omega-6 fats. Choose saturated fats like grass fed butter, tallow and ghee to maintain the integrity of your milk.
Also, make sure you’re getting enough carbohydrates, at least 250 grams per day for most adults, to prevent metabolic stress that could affect milk supply. Your diet matters — when you eat well, your baby benefits.
• Avoid unnecessary antibiotics and medications early on — Antibiotics wipe out both harmful and beneficial bacteria, which sets back the development of your baby’s gut microbiome. Unless absolutely necessary, avoid giving antibiotics in the first year of life. Common medications like acetaminophen and reflux drugs also disrupt gut bacteria and must be used sparingly.
Instead, focus on natural remedies for minor illnesses and let your baby’s immune system build resilience through proper nutrition and breastfeeding. Certain maternal medications also alter the quality of your breastmilk. Learn more in this article, “How Maternal Medications Alter Breastmilk Nutrients.”
• Reduce your exposure to PFAS — There are recent studies that found polyfluoroalkyl or perfluoroalkyl chemicals (PFAS), or "forever chemicals," used in consumer products are found in breastmilk, and can be transferred to infants.13
The best thing to do is to significantly reduce your exposure to these synthetic chemicals to lower your toxic burden and reduce the PFAS in your breastmilk. For more information about this, read “Scientists Uncover How Forever Chemicals Pass from Mother to Child.”
Breastfeeding is one of the most effective ways to set your child up for a lifetime of better health. However, I understand that not all moms can breastfeed. Those who didn't breastfeed from the start, or who have stopped for weeks or months, may find it difficult to go back to breastfeeding, as you cannot restart lactation at will. In this case, resorting to formula milk may be the only choice.
But instead of buying commercially sold infant formula, I recommend making your own formula instead. Check out “US Pushed Countries to Weaken Infant Formula Regulations, Documents Show” for my recommended formula milk recipe, which you can make at home.
Frequently Asked Questions (FAQs) About the Benefits of Breastmilk
Q: How does breastfeeding affect my infant’s gut microbiome?
A: Breastfeeding increases the diversity of beneficial gut bacteria, particularly Bifidobacterium, which helps maintain your baby’s gut health, supports immune function, and reduces inflammation. This balanced microbiome plays a key role in their long-term metabolic and cardiovascular health.
Q: Can breastfeeding lower my child’s risk of high blood pressure?
A: Yes, research shows that breastfed infants have lower blood pressure in early childhood. A one-unit increase in gut microbiome diversity during a child’s first month was linked to a 1.86 mmHg decrease in systolic blood pressure by age 6, reducing future cardiovascular risks.
Q: How does formula feeding compare to breastfeeding in terms of gut health?
A: Formula-fed infants have a less diverse gut microbiome with more inflammatory bacteria, such as Clostridium and Proteobacteria. These bacteria can contribute to gut imbalance, immune dysfunction, and higher blood pressure later in life.
Q: What makes breastmilk better than formula for immune function?
A: Breastmilk contains human milk oligosaccharides (HMOs) that selectively feed beneficial bacteria and secretory immunoglobulin A (SIgA), which strengthens the gut lining, prevents infections, and helps train the immune system to recognize harmful substances.
Q: How long should I breastfeed my child to maximize these health benefits?
A: Exclusive breastfeeding your baby for at least six months provides the greatest benefits for their gut microbiome diversity, immune development, and blood pressure regulation. Partial breastfeeding still offers advantages, but the longer and more exclusive the breastfeeding, the stronger the protective effects.