The Benefits of Breastfeeding for Mother and Baby: What the Research Shows

Advice
Written By Bobbi Daly

There is a lot of information out there about breastfeeding — some of it excellent, some of it overstated, and some of it quietly out of date. As an IBCLC, I want the information I share with families to be accurate, balanced, and grounded in current evidence.

Benefits of Breastfeeding for Your Baby

Breastfeeding and Protection Against Infection

This is the area where the research is clearest and most consistent. Breast milk is not passive nutrition. It contains antibodies, white blood cells, lactoferrin, and other immune factors that work actively in your baby's gut and airways to help fight infection.

A major review of evidence published in 2024 by the American Academy of Pediatrics found a protective association between breastfeeding and a reduced risk of moderate-to-severe respiratory and gastrointestinal infections, ear infections, allergic rhinitis, asthma, and infant mortality. American Academy of Pediatrics

Even one month of breastfeeding has been associated with a reduced likelihood of severe outcomes in infants with RSV (respiratory syncytial virus), including reduced risk of intensive care admission and the need for mechanical ventilation. RSV is one of the most common causes of bronchiolitis in babies, so this is particularly relevant for families in Ireland, where bronchiolitis season puts significant pressure on paediatric services every winter. nih

Breast milk contains immunoglobulins, lactoferrin, and lymphocytes. The protection against gut infections is especially well-documented — immunoglobulins absorbed through breastfeeding bind directly to microorganisms in the gastrointestinal tract. PubMed Central

How Breastfeeding Supports Your Baby's Gut Development

Breast milk helps shape your baby's gut microbiome in the earliest weeks of life. It contains human milk oligosaccharides — a type of complex sugar that feeds beneficial bacteria in the gut — as well as living bacteria from the mother's own microbiome. Research indicates that breastfeeding is associated with a microbial profile more compatible with healthy infant development. Research, Society and Development

This matters beyond digestion. There is a growing body of research exploring the link between gut health in infancy and longer-term outcomes including immune function, allergies, and even brain development. This is still an active area of research, and we should be cautious about overstating what we know — but the direction of the evidence is consistently positive.

Breastfeeding and Reduced Risk of Chronic Conditions in Children

The 2024 AAP systematic review found associations between breastfeeding and reduced risk of asthma, inflammatory bowel disease, type 1 diabetes, obesity, high systolic blood pressure, and childhood leukaemia. American Academy of Pediatrics

These are associations rather than proven causes, and the strength of evidence varies across conditions. But the picture that emerges across a large body of research is a consistent one — breastfeeding appears to do more than nourish a baby in the short term.

Does Breastfeeding Support Brain Development?

Research suggests that children who were breastfed tend to perform better on intelligence tests later in life and are less likely to be overweight or obese. The reasons are not fully understood, and this is a difficult area to study because many social and economic factors influence child development. Breast milk's fatty acid content, the gut-brain connection, and the closeness of the feeding relationship may all play a part. It is a promising area of research, but one that calls for some caution when interpreting individual studies. MDPI

Benefits of Breastfeeding for Mothers

How Breastfeeding Supports Physical Recovery After Birth

One of the most immediate physical benefits of breastfeeding is its effect on the uterus. When a baby feeds at the breast, the mother's body releases oxytocin, which causes the uterus to contract. These contractions are essential for uterine involution — the process by which the uterus returns to its pre-pregnancy size — and are directly stimulated by nipple contact during breastfeeding. This is why many mothers notice afterpains during feeding, particularly in the first few days. It is a sign that the body is doing exactly what it should. Frontiers

Breastfeeding and Reduced Risk of Breast and Ovarian Cancer

Research consistently shows a reduced risk of breast cancer associated with breastfeeding, particularly for those who breastfeed for 12 months or longer, with the protective effect linked to hormonal, immunological, and physiological changes during lactation. nih

Evidence also supports an association between breastfeeding and lower rates of epithelial ovarian cancer. Effective Health Care

Breastfeeding and Reduced Risk of Type 2 Diabetes and Hypertension

A meta-analysis of studies involving more than 200,000 participants found that breastfeeding was associated with a 30% reduction in risk of type 2 diabetes and a 13% reduction in risk of hypertension in mothers. nih

Breastfeeding and Cardiovascular Health in Mothers

A systematic review and meta-analysis involving data from over 1.1 million women found that those who had ever breastfed had lower rates of cardiovascular disease, coronary heart disease, stroke, and fatal cardiovascular events compared to those who had never breastfed. The researchers noted that the quality of evidence ranged from very low to moderate — so this finding is best understood as part of a broader picture rather than a standalone conclusion. nih

Breastfeeding and Maternal Mental Health: A Nuanced Picture

Breastfeeding is associated with the release of oxytocin and prolactin, both of which have calming, mood-supporting effects. Some evidence points to a reduction in the risk of postnatal depression among breastfeeding mothers, with a possible risk reduction of around 14%, potentially related to the hormonal effects of prolactin and oxytocin. nih

That said, this relationship is not straightforward. For some mothers, breastfeeding difficulties are a significant source of stress, and struggling with feeding can contribute to low mood. Research has identified breastfeeding self-efficacy, social support, and the quality of the feeding relationship as important factors — which is why having good support in place from early on makes such a difference. PubMed

Antenatal Breastfeeding Preparation in Kerry

If you are pregnant and planning to breastfeed, an antenatal breastfeeding consultation can be one of the most useful things you do before your baby arrives. It gives you the chance to ask questions, understand what to expect in the early days, and feel genuinely prepared — rather than finding your feet under pressure when you are exhausted and a new baby has arrived.

You can find out more about my Breastfeeding Preparation Intensive Consultation here.

Key sources:

Bobbi Daly
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