Over many years there have numerous studies that show clearly that human milk confers significant health and other advantages to infants. Obviously, nutrition is of extreme importance in early life with both international and national recommendations stating that infants should be exclusively breast fed to 6 months1or to around 6 months of age2 but importantly, that breast feeding should continue until 2 years of age or beyond for as long as the mother and child desire1.
It has been estimated that near universal breastfeeding would prevent the deaths of 823,000 children annually in low and middle income countries (LMIC) alone3. As well as significant effects on mortality, there are important effects on morbidity. For example, a 2013 review concluded that from 66 analyses mainly from LMICs, breastfeeding would reduce all diarrhoea episodes by around a half and respiratory infections by a third4.
Importantly, there are significant advantages in breastfeeding in higher income, industrialised countries as well. Reviews have shown a protective effect of breast feeding, in such countries, on both respiratory and gastrointestinal infections5. Specifically, in their review, Duijts and colleagues5 reported that in data collected from industrialised countries, including the UK, Canada and the USA, six out of eight studies suggested that breastfeeding had a protective effect against gastrointestinal infections. For respiratory tract infections, data collected from 16 studies from countries including Australia, the USA, Italy and Canada revealed that 13 of the 16 studies found a protective effect of breast feeding.
A more recent study in 2020, has also reported that an increased duration of breast feeding, especially exclusive breast feeding, protects against infections requiring hospitalisation in the first year of life 6
Finally, in term infants, one of the most quoted benefits of breastfeeding in term infants, is the lower risk of overweight and obesity in these infants and children. Numerous studies, over many years, have reported this advantage7-10. It is noteworthy that whilst many such studies show that breast feeding per se, is advantageous there is a significant literature that shows that prolonged any breast feeding has a protective effect against overweight and obesity.11-15. This highlights the importance of the recommendation mentioned earlier that that breast feeding should continue until 2 years of age or beyond for as long as the mother and child desire1.
The advantages of human milk also extends to significant health benefits in premature infants with studies showing that such infants fed human milk have better growth outcomes and reduced incidence of necrotising enterocolitis16,17.
It should not be forgotten that there are significant health benefits to breastfeeding mothers, with a systematic review published in 2015 reporting important reductions in the risk of both ovarian and breast cancer in breastfeeding mothers as well as reductions in risk of type 2 diabetes18. Once again longer term any breast feeding has been shown to be advantageous to the mother. Breast feeding for more than 12 months was associated with a reduced risk of breast cancer by 26% and ovarian cancer by 37%. Breast feeding was reported to be associated with a 32% lower risk of type 2 diabetes.
A recent 2019 study from Australia19 using data from over 100,000 women showed clearly that ever breast feeding was associated with both a lower risk of cardiovascular disease (CVD) hospitalisation and CVD mortality when compared with mothers who had never breast fed. These authors also concluded that breast feeding < 12 months/child was significantly associated with a lower risk of CVD hospitalisation.
Data and evidence from the worldwide scientific literature strongly supports the international and national recommendations that infants should be exclusively breast fed to 6 months1 or to around 6 months of age2 but importantly, that breast feeding should continue until 2 years of age or beyond for as long as the mother and child desire1. Mothers and families should be supported in their efforts to follow these recommendations for the best short-term and long-term health outcomes for both child and mother.